From: Denis Vlasenko Date: Fri, 23 Nov 2007 23:28:55 +0000 (-0000) Subject: kill lash. "lash" builtin still exists, but it runs hush. X-Git-Tag: 1_9_0~68 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=96702ca945a8deac1f989584f2b25d1a16d14b72;p=oweals%2Fbusybox.git kill lash. "lash" builtin still exists, but it runs hush. --- diff --git a/TODO b/TODO index 10ed7e0d5..52a4aad11 100644 --- a/TODO +++ b/TODO @@ -22,12 +22,9 @@ Rob Landley : The command shell situation is a big mess. We have three or four different shells that don't really share any code, and the "standalone shell" doesn't work all that well (especially not in a chroot environment), due to apps not - being reentrant. I'm writing a new shell (bbsh) to unify the various - shells and configurably add the minimal set of bash features people - actually use. The hardest part is it has to configure down as small as - lash while providing lash's features. The rest is easy in comparison. - bzip2 - Compression-side support. + being reentrant. + lash is phased out. hush can be configured down to be nearly as small, + but less buggy :) init General cleanup (should use ENABLE_FEATURE_INIT_SYSLOG and ENABLE_FEATURE_INIT_DEBUG). depmod @@ -35,8 +32,6 @@ Rob Landley : use of the depmod.pl (perl is to bloated for most embedded setups) and or orig modutils. The orig depmod is rather pointless to have to add to a firmware image in when we already have a insmod/rmmod and friends. - Unify base64 handling. - [done] Do a SUSv3 audit Look at the full Single Unix Specification version 3 (available online at "http://www.opengroup.org/onlinepubs/009695399/nfindex.html") and diff --git a/include/applets.h b/include/applets.h index 757fa4a25..8fdf1a241 100644 --- a/include/applets.h +++ b/include/applets.h @@ -312,7 +312,6 @@ USE_SETSID(APPLET(setsid, _BB_DIR_USR_BIN, _BB_SUID_NEVER)) USE_SETUIDGID(APPLET_ODDNAME(setuidgid, chpst, _BB_DIR_USR_BIN, _BB_SUID_NEVER, setuidgid)) USE_FEATURE_SH_IS_ASH(APPLET_NOUSAGE(sh, ash, _BB_DIR_BIN, _BB_SUID_NEVER)) USE_FEATURE_SH_IS_HUSH(APPLET_NOUSAGE(sh, hush, _BB_DIR_BIN, _BB_SUID_NEVER)) -USE_FEATURE_SH_IS_LASH(APPLET_NOUSAGE(sh, lash, _BB_DIR_BIN, _BB_SUID_NEVER)) USE_FEATURE_SH_IS_MSH(APPLET_NOUSAGE(sh, msh, _BB_DIR_BIN, _BB_SUID_NEVER)) USE_SHA1SUM(APPLET_ODDNAME(sha1sum, md5_sha1_sum, _BB_DIR_USR_BIN, _BB_SUID_NEVER, sha1sum)) USE_SLATTACH(APPLET(slattach, _BB_DIR_SBIN, _BB_SUID_NEVER)) diff --git a/include/usage.h b/include/usage.h index 82a17578a..d910e2bf6 100644 --- a/include/usage.h +++ b/include/usage.h @@ -3194,15 +3194,7 @@ USE_FEATURE_RUN_PARTS_FANCY("\n -l Prints names of all matching files even when "[FILE]...\n" \ "or: sh -c command [args]..." #define lash_full_usage \ - "The BusyBox LAme SHell (command interpreter)" -#define lash_notes_usage \ - "This command does not yet have proper documentation.\n\n" \ - "Use lash just as you would use any other shell. It properly handles pipes,\n" \ - "redirects, job control, can be used as the shell for scripts, and has a\n" \ - "sufficient set of builtins to do what is needed. It does not (yet) support\n" \ - "Bourne Shell syntax. If you need things like \"if-then-else\", \"while\", and such\n" \ - "use ash or bash. If you just need a very simple and extremely small shell,\n" \ - "this will do the job." + "lash is deprecated, please use hush" #define last_trivial_usage \ "" diff --git a/shell/Config.in b/shell/Config.in index 312583e87..9328c9102 100644 --- a/shell/Config.in +++ b/shell/Config.in @@ -20,9 +20,9 @@ config FEATURE_SH_IS_HUSH select HUSH bool "hush" -config FEATURE_SH_IS_LASH - select LASH - bool "lash" +####config FEATURE_SH_IS_LASH +#### select LASH +#### bool "lash" config FEATURE_SH_IS_MSH select MSH @@ -229,16 +229,9 @@ config HUSH_LOOPS config LASH bool "lash" default n - select TRUE - select FALSE - select TEST + select HUSH help - lash is the very smallest shell (adds just 10k) and it is quite - usable as a command prompt, but it is not suitable for any but the - most trivial scripting (such as an initrd that calls insmod a few - times) since it does not understand any Bourne shell grammar. It - does handle pipes, redirects, and job control though. Adding in - command editing makes it a very nice lightweight command prompt. + lash is deprecated and will be removed, please migrate to hush. config MSH diff --git a/shell/Kbuild b/shell/Kbuild index 944eaff51..36a8ffd3a 100644 --- a/shell/Kbuild +++ b/shell/Kbuild @@ -7,7 +7,6 @@ lib-y:= lib-$(CONFIG_ASH) += ash.o lib-$(CONFIG_HUSH) += hush.o -lib-$(CONFIG_LASH) += lash.o lib-$(CONFIG_MSH) += msh.o lib-$(CONFIG_CTTYHACK) += cttyhack.o diff --git a/shell/hush.c b/shell/hush.c index 6bf4d1d19..b3c77aa14 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -3925,3 +3925,13 @@ int hush_main(int argc, char **argv) #endif hush_exit(opt ? opt : last_return_code); } + + +#if ENABLE_LASH +int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int lash_main(int argc, char **argv) +{ + //bb_error_msg("lash is deprecated, please use hush instead"); + return hush_main(argc, argv); +} +#endif diff --git a/shell/lash.c b/shell/lash.c deleted file mode 100644 index 781dfdb5a..000000000 --- a/shell/lash.c +++ /dev/null @@ -1,1570 +0,0 @@ -/* vi: set sw=4 ts=4: */ -/* - * lash -- the BusyBox Lame-Ass SHell - * - * Copyright (C) 1999-2004 by Erik Andersen - * - * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is - * under the following liberal license: "We have placed this source code in the - * public domain. Use it in any project, free or commercial." - * - * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. - */ - -/* This shell's parsing engine is officially at a dead-end. Future - * work shell work should be done using hush, msh, or ash. This is - * still a very useful, small shell -- it just don't need any more - * features beyond what it already has... - */ - -//For debugging/development on the shell only... -//#define DEBUG_SHELL - -#include -#include - -#include "busybox.h" /* for struct bb_applet */ - -#define expand_t glob_t - -/* Always enable for the moment... */ -#define CONFIG_LASH_PIPE_N_REDIRECTS -#define CONFIG_LASH_JOB_CONTROL -#define ENABLE_LASH_PIPE_N_REDIRECTS 1 -#define ENABLE_LASH_JOB_CONTROL 1 - - -enum { MAX_READ = 128 }; /* size of input buffer for 'read' builtin */ -#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" - - -#if ENABLE_LASH_PIPE_N_REDIRECTS -enum redir_type { REDIRECT_INPUT, REDIRECT_OVERWRITE, - REDIRECT_APPEND -}; -#endif - -enum { - DEFAULT_CONTEXT = 0x1, - IF_TRUE_CONTEXT = 0x2, - IF_FALSE_CONTEXT = 0x4, - THEN_EXP_CONTEXT = 0x8, - ELSE_EXP_CONTEXT = 0x10 -}; - -#define LASH_OPT_DONE (1) -#define LASH_OPT_SAW_QUOTE (2) - -#if ENABLE_LASH_PIPE_N_REDIRECTS -struct redir_struct { - enum redir_type type; /* type of redirection */ - int fd; /* file descriptor being redirected */ - char *filename; /* file to redirect fd to */ -}; -#endif - -struct child_prog { - pid_t pid; /* 0 if exited */ - char **argv; /* program name and arguments */ - int num_redirects; /* elements in redirection array */ - int is_stopped; /* is the program currently running? */ - struct job *family; /* pointer back to the child's parent job */ -#if ENABLE_LASH_PIPE_N_REDIRECTS - struct redir_struct *redirects; /* I/O redirects */ -#endif -}; - -struct jobset { - struct job *head; /* head of list of running jobs */ - struct job *fg; /* current foreground job */ -}; - -struct job { - int jobid; /* job number */ - int num_progs; /* total number of programs in job */ - int running_progs; /* number of programs running */ - char *text; /* name of job */ - char *cmdbuf; /* buffer various argv's point into */ - pid_t pgrp; /* process group ID for the job */ - struct child_prog *progs; /* array of programs in job */ - struct job *next; /* to track background commands */ - int stopped_progs; /* number of programs alive, but stopped */ - unsigned int job_context; /* bitmask defining current context */ - struct jobset *job_list; -}; - -struct built_in_command { - const char *cmd; /* name */ - const char *descr; /* description */ - int (*function) (struct child_prog *); /* function ptr */ -}; - -/* function prototypes for builtins */ -static int builtin_cd(struct child_prog *cmd); -static int builtin_exec(struct child_prog *cmd); -static int builtin_exit(struct child_prog *cmd); -static int builtin_fg_bg(struct child_prog *cmd); -static int builtin_help(struct child_prog *cmd); -static int builtin_jobs(struct child_prog *dummy); -static int builtin_pwd(struct child_prog *dummy); -static int builtin_export(struct child_prog *cmd); -static int builtin_source(struct child_prog *cmd); -static int builtin_unset(struct child_prog *cmd); -static int builtin_read(struct child_prog *cmd); - - -/* function prototypes for shell stuff */ -static void checkjobs(struct jobset *job_list); -static void remove_job(struct jobset *j_list, struct job *job); -static int get_command_bufsiz(FILE * source, char *command); -static int parse_command(char **command_ptr, struct job *job, int *inbg); -static int run_command(struct job *newjob, int inbg, int outpipe[2]); -static int pseudo_exec(struct child_prog *cmd) ATTRIBUTE_NORETURN; -static int busy_loop(FILE * input); - - -/* Table of built-in functions (these are non-forking builtins, meaning they - * can change global variables in the parent shell process but they will not - * work with pipes and redirects; 'unset foo | whatever' will not work) */ -static const struct built_in_command bltins[] = { - {"bg" , "Resume a job in the background", builtin_fg_bg}, - {"cd" , "Change working directory", builtin_cd}, - {"exec" , "Exec command, replacing this shell with the exec'd process", builtin_exec}, - {"exit" , "Exit from shell()", builtin_exit}, - {"fg" , "Bring job into the foreground", builtin_fg_bg}, - {"jobs" , "Lists the active jobs", builtin_jobs}, - {"export", "Set environment variable", builtin_export}, - {"unset" , "Unset environment variable", builtin_unset}, - {"read" , "Input environment variable", builtin_read}, - {"." , "Source-in and run commands in a file", builtin_source}, - /* These were "forked applets", but distinction was nuked */ - /* Original comment retained: */ - /* Table of forking built-in functions (things that fork cannot change global - * variables in the parent process, such as the current working directory) */ - {"pwd" , "Print current directory", builtin_pwd}, - {"help" , "List shell built-in commands", builtin_help}, - /* to do: add ulimit */ -}; - - -#define VEC_LAST(v) v[ARRAY_SIZE(v)-1] - - -static int shell_context; /* Type prompt trigger (PS1 or PS2) */ - - -/* Globals that are static to this file */ -static char *cwd; -static char *local_pending_command; -static struct jobset job_list = { NULL, NULL }; -static int global_argc; -static char **global_argv; -static llist_t *close_me_list; -static int last_return_code; -static int last_bg_pid; -static unsigned int last_jobid; -static int shell_terminal; -static const char *PS1; -static const char *PS2 = "> "; - - -#ifdef DEBUG_SHELL -static inline void debug_printf(const char *format, ...) -{ - va_list args; - va_start(args, format); - vfprintf(stderr, format, args); - va_end(args); -} -#else -static inline void debug_printf(const char ATTRIBUTE_UNUSED *format, ...) { } -#endif - -/* - Most builtins need access to the struct child_prog that has - their arguments, previously coded as cmd->progs[0]. That coding - can exhibit a bug, if the builtin is not the first command in - a pipeline: "echo foo | exec sort" will attempt to exec foo. - -builtin previous use notes ------- ----------------- --------- -cd cmd->progs[0] -exec cmd->progs[0] squashed bug: didn't look for applets or forking builtins -exit cmd->progs[0] -fg_bg cmd->progs[0], job_list->head, job_list->fg -help 0 -jobs job_list->head -pwd 0 -export cmd->progs[0] -source cmd->progs[0] -unset cmd->progs[0] -read cmd->progs[0] - -I added "struct job *family;" to struct child_prog, -and switched API to builtin_foo(struct child_prog *child); -So cmd->text becomes child->family->text - cmd->job_context becomes child->family->job_context - cmd->progs[0] becomes *child - job_list becomes child->family->job_list - */ - - -static void update_cwd(void) -{ - cwd = xrealloc_getcwd_or_warn(cwd); - if (!cwd) - cwd = xstrdup(bb_msg_unknown); -} - -/* built-in 'cd ' handler */ -static int builtin_cd(struct child_prog *child) -{ - char *newdir; - - if (child->argv[1] == NULL) - newdir = getenv("HOME"); - else - newdir = child->argv[1]; - if (chdir(newdir)) { - bb_perror_msg("cd: %s", newdir); - return EXIT_FAILURE; - } - update_cwd(); - return EXIT_SUCCESS; -} - -/* built-in 'exec' handler */ -static int builtin_exec(struct child_prog *child) -{ - if (child->argv[1] == NULL) - return EXIT_SUCCESS; /* Really? */ - child->argv++; - while (close_me_list) - close((long)llist_pop(&close_me_list)); - pseudo_exec(child); - /* never returns */ -} - -/* built-in 'exit' handler */ -static int builtin_exit(struct child_prog *child) -{ - if (child->argv[1] == NULL) - exit(EXIT_SUCCESS); - - exit(atoi(child->argv[1])); -} - -/* built-in 'fg' and 'bg' handler */ -static int builtin_fg_bg(struct child_prog *child) -{ - int i, jobnum; - struct job *job; - - /* If they gave us no args, assume they want the last backgrounded task */ - if (!child->argv[1]) { - for (job = child->family->job_list->head; job; job = job->next) { - if (job->jobid == last_jobid) { - goto found; - } - } - bb_error_msg("%s: no current job", child->argv[0]); - return EXIT_FAILURE; - } - if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) { - bb_error_msg(bb_msg_invalid_arg, child->argv[1], child->argv[0]); - return EXIT_FAILURE; - } - for (job = child->family->job_list->head; job; job = job->next) { - if (job->jobid == jobnum) { - goto found; - } - } - bb_error_msg("%s: %d: no such job", child->argv[0], jobnum); - return EXIT_FAILURE; - found: - if (*child->argv[0] == 'f') { - /* Put the job into the foreground. */ - tcsetpgrp(shell_terminal, job->pgrp); - - child->family->job_list->fg = job; - } - - /* Restart the processes in the job */ - for (i = 0; i < job->num_progs; i++) - job->progs[i].is_stopped = 0; - - job->stopped_progs = 0; - - i = kill(- job->pgrp, SIGCONT); - if (i < 0) { - if (errno == ESRCH) { - remove_job(&job_list, job); - } else { - bb_perror_msg("kill (SIGCONT)"); - } - } - - return EXIT_SUCCESS; -} - -/* built-in 'help' handler */ -static int builtin_help(struct child_prog ATTRIBUTE_UNUSED *dummy) -{ - const struct built_in_command *x; - - printf("\nBuilt-in commands:\n" - "-------------------\n"); - for (x = bltins; x <= &VEC_LAST(bltins); x++) { - if (x->descr == NULL) - continue; - printf("%s\t%s\n", x->cmd, x->descr); - } - bb_putchar('\n'); - return EXIT_SUCCESS; -} - -/* built-in 'jobs' handler */ -static int builtin_jobs(struct child_prog *child) -{ - struct job *job; - const char *status_string; - - for (job = child->family->job_list->head; job; job = job->next) { - if (job->running_progs == job->stopped_progs) - status_string = "Stopped"; - else - status_string = "Running"; - - printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text); - } - return EXIT_SUCCESS; -} - - -/* built-in 'pwd' handler */ -static int builtin_pwd(struct child_prog ATTRIBUTE_UNUSED *dummy) -{ - update_cwd(); - puts(cwd); - return EXIT_SUCCESS; -} - -/* built-in 'export VAR=value' handler */ -static int builtin_export(struct child_prog *child) -{ - int res; - char *v = child->argv[1]; - - if (v == NULL) { - char **e; - for (e = environ; *e; e++) { - puts(*e); - } - return 0; - } - res = putenv(v); - if (res) - bb_perror_msg("export"); -#if ENABLE_FEATURE_EDITING_FANCY_PROMPT - if (strncmp(v, "PS1=", 4) == 0) - PS1 = getenv("PS1"); -#endif - -#if ENABLE_LOCALE_SUPPORT - // TODO: why getenv? "" would be just as good... - if (strncmp(v, "LC_ALL=", 7) == 0) - setlocale(LC_ALL, getenv("LC_ALL")); - if (strncmp(v, "LC_CTYPE=", 9) == 0) - setlocale(LC_CTYPE, getenv("LC_CTYPE")); -#endif - - return res; -} - -/* built-in 'read VAR' handler */ -static int builtin_read(struct child_prog *child) -{ - int res = 0, len; - char *s; - char string[MAX_READ]; - - if (child->argv[1]) { - /* argument (VAR) given: put "VAR=" into buffer */ - safe_strncpy(string, child->argv[1], MAX_READ-1); - len = strlen(string); - string[len++] = '='; - string[len] = '\0'; - fgets(&string[len], sizeof(string) - len, stdin); /* read string */ - res = strlen(string); - if (res > len) - string[--res] = '\0'; /* chomp trailing newline */ - /* - ** string should now contain "VAR=" - ** copy it (putenv() won't do that, so we must make sure - ** the string resides in a static buffer!) - */ - res = -1; - s = strdup(string); - if (s) - res = putenv(s); - if (res) - bb_perror_msg("read"); - } else - fgets(string, sizeof(string), stdin); - - return res; -} - -/* Built-in '.' handler (read-in and execute commands from file) */ -static int builtin_source(struct child_prog *child) -{ - FILE *input; - int status; - - input = fopen_or_warn(child->argv[1], "r"); - if (!input) { - return EXIT_FAILURE; - } - - llist_add_to(&close_me_list, (void *)(long)fileno(input)); - /* Now run the file */ - status = busy_loop(input); - fclose(input); - llist_pop(&close_me_list); - return status; -} - -/* built-in 'unset VAR' handler */ -static int builtin_unset(struct child_prog *child) -{ - if (child->argv[1] == NULL) { - printf(bb_msg_requires_arg, "unset"); - return EXIT_FAILURE; - } - unsetenv(child->argv[1]); - return EXIT_SUCCESS; -} - -#if ENABLE_LASH_JOB_CONTROL -/* free up all memory from a job */ -static void free_job(struct job *cmd) -{ - int i; - struct jobset *keep; - - for (i = 0; i < cmd->num_progs; i++) { - free(cmd->progs[i].argv); -#if ENABLE_LASH_PIPE_N_REDIRECTS - free(cmd->progs[i].redirects); -#endif - } - free(cmd->progs); - free(cmd->text); - free(cmd->cmdbuf); - keep = cmd->job_list; - memset(cmd, 0, sizeof(struct job)); - cmd->job_list = keep; -} - -/* remove a job from a jobset */ -static void remove_job(struct jobset *j_list, struct job *job) -{ - struct job *prevjob; - - free_job(job); - if (job == j_list->head) { - j_list->head = job->next; - } else { - prevjob = j_list->head; - while (prevjob->next != job) - prevjob = prevjob->next; - prevjob->next = job->next; - } - - if (j_list->head) - last_jobid = j_list->head->jobid; - else - last_jobid = 0; - - free(job); -} - -/* Checks to see if any background processes have exited -- if they - have, figure out why and see if a job has completed */ -static void checkjobs(struct jobset *j_list) -{ - struct job *job; - pid_t childpid; - int status; - int prognum = 0; - - while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) { - for (job = j_list->head; job; job = job->next) { - prognum = 0; - while (prognum < job->num_progs && - job->progs[prognum].pid != childpid) prognum++; - if (prognum < job->num_progs) - break; - } - - /* This happens on backticked commands */ - if (job == NULL) - return; - - if (WIFEXITED(status) || WIFSIGNALED(status)) { - /* child exited */ - job->running_progs--; - job->progs[prognum].pid = 0; - - if (!job->running_progs) { - printf(JOB_STATUS_FORMAT, job->jobid, "Done", job->text); - last_jobid = 0; - remove_job(j_list, job); - } - } else { - /* child stopped */ - job->stopped_progs++; - job->progs[prognum].is_stopped = 1; - } - } - - if (childpid == -1 && errno != ECHILD) - bb_perror_msg("waitpid"); -} -#else -static void checkjobs(struct jobset *j_list) -{ -} -static void free_job(struct job *cmd) -{ -} -static void remove_job(struct jobset *j_list, struct job *job) -{ -} -#endif - -#if ENABLE_LASH_PIPE_N_REDIRECTS -/* squirrel != NULL means we squirrel away copies of stdin, stdout, - * and stderr if they are redirected. */ -static int setup_redirects(struct child_prog *prog, int squirrel[]) -{ - int i; - int openfd; - int mode = O_RDONLY; - struct redir_struct *redir = prog->redirects; - - for (i = 0; i < prog->num_redirects; i++, redir++) { - switch (redir->type) { - case REDIRECT_INPUT: - mode = O_RDONLY; - break; - case REDIRECT_OVERWRITE: - mode = O_WRONLY | O_CREAT | O_TRUNC; - break; - case REDIRECT_APPEND: - mode = O_WRONLY | O_CREAT | O_APPEND; - break; - } - - openfd = open3_or_warn(redir->filename, mode, 0666); - if (openfd < 0) { - /* this could get lost if stderr has been redirected, but - bash and ash both lose it as well (though zsh doesn't!) */ - return 1; - } - - if (openfd != redir->fd) { - if (squirrel && redir->fd < 3) { - squirrel[redir->fd] = dup(redir->fd); - close_on_exec_on(squirrel[redir->fd]); - } - dup2(openfd, redir->fd); - close(openfd); - } - } - - return 0; -} - -static void restore_redirects(int squirrel[]) -{ - int i, fd; - for (i = 0; i < 3; i++) { - fd = squirrel[i]; - if (fd != -1) { - /* No error checking. I sure wouldn't know what - * to do with an error if I found one! */ - dup2(fd, i); - close(fd); - } - } -} -#else -static inline int setup_redirects(struct child_prog *prog, int squirrel[]) -{ - return 0; -} -static inline void restore_redirects(int squirrel[]) -{ -} -#endif - -static inline void cmdedit_set_initial_prompt(void) -{ -#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT - PS1 = NULL; -#else - PS1 = getenv("PS1"); - if (PS1 == 0) - PS1 = "\\w \\$ "; -#endif -} - -static inline const char* setup_prompt_string(void) -{ -#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT - /* Set up the prompt */ - if (shell_context == 0) { - char *ns; - free((char*)PS1); - ns = xmalloc(strlen(cwd)+4); - sprintf(ns, "%s %c ", cwd, (geteuid() != 0) ? '$': '#'); - PS1 = ns; - return ns; - } else { - return PS2; - } -#else - return (shell_context == 0)? PS1 : PS2; -#endif -} - -#if ENABLE_FEATURE_EDITING -static line_input_t *line_input_state; -#endif - -static int get_command_bufsiz(FILE * source, char *command) -{ - const char *prompt_str; - - if (source == NULL) { - if (local_pending_command) { - /* a command specified (-c option): return it & mark it done */ - strncpy(command, local_pending_command, BUFSIZ); - local_pending_command = NULL; - return 0; - } - return 1; - } - - if (source == stdin) { - prompt_str = setup_prompt_string(); - -#if ENABLE_FEATURE_EDITING - /* - ** enable command line editing only while a command line - ** is actually being read; otherwise, we'll end up bequeathing - ** atexit() handlers and other unwanted stuff to our - ** child processes (rob@sysgo.de) - */ - read_line_input(prompt_str, command, BUFSIZ, line_input_state); - return 0; -#else - fputs(prompt_str, stdout); -#endif - } - - if (!fgets(command, BUFSIZ - 2, source)) { - if (source == stdin) - bb_putchar('\n'); - return 1; - } - - return 0; -} - -static char * strsep_space(char *string, int * ix) -{ - /* Short circuit the trivial case */ - if (!string || ! string[*ix]) - return NULL; - - /* Find the end of the token. */ - while (string[*ix] && !isspace(string[*ix]) ) { - (*ix)++; - } - - /* Find the end of any whitespace trailing behind - * the token and let that be part of the token */ - while (string[*ix] && (isspace)(string[*ix]) ) { - (*ix)++; - } - - if (!*ix) { - /* Nothing useful was found */ - return NULL; - } - - return xstrndup(string, *ix); -} - -static int expand_arguments(char *command) -{ - static const char out_of_space[] ALIGN1 = "out of space during expansion"; - - int total_length = 0, length, i, retval, ix = 0; - expand_t expand_result; - char *tmpcmd, *cmd, *cmd_copy; - char *src, *dst, *var; - int flags = GLOB_NOCHECK -#ifdef GLOB_BRACE - | GLOB_BRACE -#endif -#ifdef GLOB_TILDE - | GLOB_TILDE -#endif - ; - - /* get rid of the terminating \n */ - chomp(command); - - /* Fix up escape sequences to be the Real Thing(tm) */ - while (command && command[ix]) { - if (command[ix] == '\\') { - const char *tmp = command+ix+1; - command[ix] = bb_process_escape_sequence( &tmp ); - memmove(command+ix + 1, tmp, strlen(tmp)+1); - } - ix++; - } - /* Use glob and then fixup environment variables and such */ - - /* It turns out that glob is very stupid. We have to feed it one word at a - * time since it can't cope with a full string. Here we convert command - * (char*) into cmd (char**, one word per string) */ - - /* We need a clean copy, so strsep can mess up the copy while - * we write stuff into the original (in a minute) */ - cmd = cmd_copy = xstrdup(command); - *command = '\0'; - for (ix = 0, tmpcmd = cmd; - (tmpcmd = strsep_space(cmd, &ix)) != NULL; cmd += ix, ix = 0) { - if (*tmpcmd == '\0') - break; - /* we need to trim() the result for glob! */ - trim(tmpcmd); - retval = glob(tmpcmd, flags, NULL, &expand_result); - free(tmpcmd); /* Free mem allocated by strsep_space */ - if (retval == GLOB_NOSPACE) { - /* Mem may have been allocated... */ - globfree(&expand_result); - bb_error_msg(out_of_space); - return FALSE; - } else if (retval != 0) { - /* Some other error. GLOB_NOMATCH shouldn't - * happen because of the GLOB_NOCHECK flag in - * the glob call. */ - bb_error_msg("syntax error"); - return FALSE; - } else { - /* Convert from char** (one word per string) to a simple char*, - * but don't overflow command which is BUFSIZ in length */ - for (i = 0; i < expand_result.gl_pathc; i++) { - length = strlen(expand_result.gl_pathv[i]); - if (total_length+length+1 >= BUFSIZ) { - bb_error_msg(out_of_space); - return FALSE; - } - strcat(command+total_length, " "); - total_length += 1; - strcat(command+total_length, expand_result.gl_pathv[i]); - total_length += length; - } - globfree(&expand_result); - } - } - free(cmd_copy); - trim(command); - - /* Now do the shell variable substitutions which - * wordexp can't do for us, namely $? and $! */ - src = command; - while ((dst = strchr(src,'$')) != NULL) { - var = NULL; - switch (*(dst+1)) { - case '?': - var = itoa(last_return_code); - break; - case '!': - if (last_bg_pid == -1) - *var = '\0'; - else - var = itoa(last_bg_pid); - break; - /* Everything else like $$, $#, $[0-9], etc. should all be - * expanded by wordexp(), so we can in theory skip that stuff - * here, but just to be on the safe side (i.e., since uClibc - * wordexp doesn't do this stuff yet), lets leave it in for - * now. */ - case '$': - var = itoa(getpid()); - break; - case '#': - var = itoa(global_argc - 1); - break; - case '0':case '1':case '2':case '3':case '4': - case '5':case '6':case '7':case '8':case '9': - { - int ixx = *(dst+1)-48+1; - if (ixx >= global_argc) { - var = '\0'; - } else { - var = global_argv[ixx]; - } - } - break; - - } - if (var) { - /* a single character construction was found, and - * already handled in the case statement */ - src = dst + 2; - } else { - /* Looks like an environment variable */ - char delim_hold; - int num_skip_chars = 0; - int dstlen = strlen(dst); - /* Is this a ${foo} type variable? */ - if (dstlen >= 2 && *(dst+1) == '{') { - src = strchr(dst+1, '}'); - num_skip_chars = 1; - } else { - src = dst + 1; - while ((isalnum)(*src) || *src == '_') src++; - } - if (src == NULL) { - src = dst+dstlen; - } - delim_hold = *src; - *src = '\0'; /* temporary */ - var = getenv(dst + 1 + num_skip_chars); - *src = delim_hold; - src += num_skip_chars; - } - if (var == NULL) { - /* Seems we got an un-expandable variable. So delete it. */ - var = (char*)""; - } - { - int subst_len = strlen(var); - int trail_len = strlen(src); - if (dst+subst_len+trail_len >= command+BUFSIZ) { - bb_error_msg(out_of_space); - return FALSE; - } - /* Move stuff to the end of the string to accommodate - * filling the created gap with the new stuff */ - memmove(dst+subst_len, src, trail_len+1); - /* Now copy in the new stuff */ - memcpy(dst, var, subst_len); - src = dst+subst_len; - } - } - - return TRUE; -} - -/* Return cmd->num_progs as 0 if no command is present (e.g. an empty - line). If a valid command is found, command_ptr is set to point to - the beginning of the next command (if the original command had more - then one job associated with it) or NULL if no more commands are - present. */ -static int parse_command(char **command_ptr, struct job *job, int *inbg) -{ - char *command; - char *return_command = NULL; - char *src, *buf; - int argc_l; - int flag; - int argv_alloced; - char quote = '\0'; - struct child_prog *prog; -#if ENABLE_LASH_PIPE_N_REDIRECTS - int i; - char *chptr; -#endif - - /* skip leading white space */ - *command_ptr = skip_whitespace(*command_ptr); - - /* this handles empty lines or leading '#' characters */ - if (!**command_ptr || (**command_ptr == '#')) { - job->num_progs = 0; - return 0; - } - - *inbg = 0; - job->num_progs = 1; - job->progs = xmalloc(sizeof(*job->progs)); - - /* We set the argv elements to point inside of this string. The - memory is freed by free_job(). Allocate twice the original - length in case we need to quote every single character. - - Getting clean memory relieves us of the task of NULL - terminating things and makes the rest of this look a bit - cleaner (though it is, admittedly, a tad less efficient) */ - job->cmdbuf = command = xzalloc(2*strlen(*command_ptr) + 1); - job->text = NULL; - - prog = job->progs; - prog->num_redirects = 0; - prog->is_stopped = 0; - prog->family = job; -#if ENABLE_LASH_PIPE_N_REDIRECTS - prog->redirects = NULL; -#endif - - argv_alloced = 5; - prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced); - prog->argv[0] = job->cmdbuf; - - flag = argc_l = 0; - buf = command; - src = *command_ptr; - while (*src && !(flag & LASH_OPT_DONE)) { - if (quote == *src) { - quote = '\0'; - } else if (quote) { - if (*src == '\\') { - src++; - if (!*src) { - bb_error_msg("character expected after \\"); - free_job(job); - return 1; - } - - /* in shell, "\'" should yield \' */ - if (*src != quote) { - *buf++ = '\\'; - *buf++ = '\\'; - } - } else if (*src == '*' || *src == '?' || *src == '[' || - *src == ']') *buf++ = '\\'; - *buf++ = *src; - } else if (isspace(*src)) { - if (*prog->argv[argc_l] || (flag & LASH_OPT_SAW_QUOTE)) { - buf++, argc_l++; - /* +1 here leaves room for the NULL which ends argv */ - if ((argc_l + 1) == argv_alloced) { - argv_alloced += 5; - prog->argv = xrealloc(prog->argv, - sizeof(*prog->argv) * argv_alloced); - } - prog->argv[argc_l] = buf; - flag ^= LASH_OPT_SAW_QUOTE; - } - } else - switch (*src) { - case '"': - case '\'': - quote = *src; - flag |= LASH_OPT_SAW_QUOTE; - break; - - case '#': /* comment */ - if (*(src-1)== '$') - *buf++ = *src; - else - flag |= LASH_OPT_DONE; - break; - -#if ENABLE_LASH_PIPE_N_REDIRECTS - case '>': /* redirects */ - case '<': - i = prog->num_redirects++; - prog->redirects = xrealloc(prog->redirects, - sizeof(*prog->redirects) * (i + 1)); - - prog->redirects[i].fd = -1; - if (buf != prog->argv[argc_l]) { - /* the stuff before this character may be the file number - being redirected */ - prog->redirects[i].fd = - strtol(prog->argv[argc_l], &chptr, 10); - - if (*chptr && *prog->argv[argc_l]) { - buf++, argc_l++; - prog->argv[argc_l] = buf; - } - } - - if (prog->redirects[i].fd == -1) { - if (*src == '>') - prog->redirects[i].fd = 1; - else - prog->redirects[i].fd = 0; - } - - if (*src++ == '>') { - if (*src == '>') - prog->redirects[i].type = - REDIRECT_APPEND, src++; - else - prog->redirects[i].type = REDIRECT_OVERWRITE; - } else { - prog->redirects[i].type = REDIRECT_INPUT; - } - - /* This isn't POSIX sh compliant. Oh well. */ - chptr = src; - chptr = skip_whitespace(chptr); - - if (!*chptr) { - bb_error_msg("file name expected after %c", *(src-1)); - free_job(job); - job->num_progs = 0; - return 1; - } - - prog->redirects[i].filename = buf; - while (*chptr && !isspace(*chptr)) - *buf++ = *chptr++; - - src = chptr - 1; /* we src++ later */ - prog->argv[argc_l] = ++buf; - break; - - case '|': /* pipe */ - /* finish this command */ - if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE) - argc_l++; - if (!argc_l) { - goto empty_command_in_pipe; - } - prog->argv[argc_l] = NULL; - - /* and start the next */ - job->num_progs++; - job->progs = xrealloc(job->progs, - sizeof(*job->progs) * job->num_progs); - prog = job->progs + (job->num_progs - 1); - prog->num_redirects = 0; - prog->redirects = NULL; - prog->is_stopped = 0; - prog->family = job; - argc_l = 0; - - argv_alloced = 5; - prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced); - prog->argv[0] = ++buf; - - src++; - src = skip_whitespace(src); - - if (!*src) { -empty_command_in_pipe: - bb_error_msg("empty command in pipe"); - free_job(job); - job->num_progs = 0; - return 1; - } - src--; /* we'll ++ it at the end of the loop */ - - break; -#endif - -#if ENABLE_LASH_JOB_CONTROL - case '&': /* background */ - *inbg = 1; - /* fallthrough */ -#endif - case ';': /* multiple commands */ - flag |= LASH_OPT_DONE; - return_command = *command_ptr + (src - *command_ptr) + 1; - break; - - case '\\': - src++; - if (!*src) { - bb_error_msg("character expected after \\"); - free_job(job); - return 1; - } - if (*src == '*' || *src == '[' || *src == ']' - || *src == '?') *buf++ = '\\'; - /* fallthrough */ - default: - *buf++ = *src; - } - - src++; - } - - if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE) { - argc_l++; - } - if (!argc_l) { - free_job(job); - return 0; - } - prog->argv[argc_l] = NULL; - - if (!return_command) { - job->text = xstrdup(*command_ptr); - } else { - /* This leaves any trailing spaces, which is a bit sloppy */ - job->text = xstrndup(*command_ptr, return_command - *command_ptr); - } - - *command_ptr = return_command; - - return 0; -} - -/* Run the child_prog, no matter what kind of command it uses. - */ -static int pseudo_exec(struct child_prog *child) -{ - const struct built_in_command *x; - - /* Check if the command matches any of the non-forking builtins. - * Depending on context, this might be redundant. But it's - * easier to waste a few CPU cycles than it is to figure out - * if this is one of those cases. - */ - /* Check if the command matches any of the forking builtins. */ - for (x = bltins; x <= &VEC_LAST(bltins); x++) { - if (strcmp(child->argv[0], x->cmd) == 0) { - _exit(x->function(child)); - } - } - - /* Check if the command matches any busybox internal - * commands ("applets") here. Following discussions from - * November 2000 on busybox@busybox.net, don't use - * bb_get_last_path_component_nostrip(). This way explicit - * (with slashes) filenames will never be interpreted as an - * applet, just like with builtins. This way the user can - * override an applet with an explicit filename reference. - * The only downside to this change is that an explicit - * /bin/foo invocation will fork and exec /bin/foo, even if - * /bin/foo is a symlink to busybox. - */ - if (ENABLE_FEATURE_SH_STANDALONE) { - run_applet_and_exit(child->argv[0], child->argv); - } - - execvp(child->argv[0], child->argv); - - /* Do not use bb_perror_msg_and_die() here, since we must not - * call exit() but should call _exit() instead */ - bb_simple_perror_msg(child->argv[0]); - _exit(EXIT_FAILURE); -} - -static void insert_job(struct job *newjob, int inbg) -{ - struct job *thejob; - struct jobset *j_list = newjob->job_list; - - /* find the ID for thejob to use */ - newjob->jobid = 1; - for (thejob = j_list->head; thejob; thejob = thejob->next) - if (thejob->jobid >= newjob->jobid) - newjob->jobid = thejob->jobid + 1; - - /* add thejob to the list of running jobs */ - if (!j_list->head) { - thejob = j_list->head = xmalloc(sizeof(*thejob)); - } else { - for (thejob = j_list->head; thejob->next; thejob = thejob->next) /* nothing */; - thejob->next = xmalloc(sizeof(*thejob)); - thejob = thejob->next; - } - - *thejob = *newjob; /* physically copy the struct job */ - thejob->next = NULL; - thejob->running_progs = thejob->num_progs; - thejob->stopped_progs = 0; - -#if ENABLE_LASH_JOB_CONTROL - if (inbg) { - /* we don't wait for background thejobs to return -- append it - to the list of backgrounded thejobs and leave it alone */ - printf("[%d] %d\n", thejob->jobid, - newjob->progs[newjob->num_progs - 1].pid); - last_jobid = newjob->jobid; - last_bg_pid = newjob->progs[newjob->num_progs - 1].pid; - } else { - newjob->job_list->fg = thejob; - - /* move the new process group into the foreground */ - /* Ignore errors since child could have already exited */ - tcsetpgrp(shell_terminal, newjob->pgrp); - } -#endif -} - -static int run_command(struct job *newjob, int inbg, int outpipe[2]) -{ - /* struct job *thejob; */ - int i; - int nextin, nextout; - int pipefds[2]; /* pipefd[0] is for reading */ - const struct built_in_command *x; - struct child_prog *child; - - nextin = 0; - for (i = 0; i < newjob->num_progs; i++) { - child = &(newjob->progs[i]); - - nextout = 1; - if ((i + 1) < newjob->num_progs) { - xpipe(pipefds); - nextout = pipefds[1]; - } else if (outpipe[1] != -1) { - nextout = outpipe[1]; - } - - /* Check if the command matches any non-forking builtins, - * but only if this is a simple command. - * Non-forking builtins within pipes have to fork anyway, - * and are handled in pseudo_exec. "echo foo | read bar" - * is doomed to failure, and doesn't work on bash, either. - */ - if (newjob->num_progs == 1) { - int rcode; - int squirrel[] = {-1, -1, -1}; - - /* Check if the command sets an environment variable. */ - if (strchr(child->argv[0], '=') != NULL) { - child->argv[1] = child->argv[0]; - return builtin_export(child); - } - - for (x = bltins; x <= &VEC_LAST(bltins); x++) { - if (strcmp(child->argv[0], x->cmd) == 0) { - setup_redirects(child, squirrel); - rcode = x->function(child); - restore_redirects(squirrel); - return rcode; - } - } -#if ENABLE_FEATURE_SH_STANDALONE - { - const struct bb_applet *a = find_applet_by_name(child->argv[i]); - if (a && a->nofork) { - setup_redirects(child, squirrel); - rcode = run_nofork_applet(a, child->argv + i); - restore_redirects(squirrel); - return rcode; - } - } -#endif - } - -#if BB_MMU - child->pid = fork(); -#else - child->pid = vfork(); -#endif - if (!child->pid) { - /* Set the handling for job control signals back to the default. */ - signal(SIGINT, SIG_DFL); - signal(SIGQUIT, SIG_DFL); - signal(SIGTSTP, SIG_DFL); - signal(SIGTTIN, SIG_DFL); - signal(SIGTTOU, SIG_DFL); - signal(SIGCHLD, SIG_DFL); - - /* Close all open filehandles. */ - while (close_me_list) - close((long)llist_pop(&close_me_list)); - - if (outpipe[1] != -1) { - close(outpipe[0]); - } - if (nextin != 0) { - dup2(nextin, 0); - close(nextin); - } - - if (nextout != 1) { - dup2(nextout, 1); - dup2(nextout, 2); /* Really? */ - close(nextout); - close(pipefds[0]); - } - - /* explicit redirects override pipes */ - setup_redirects(child,NULL); - - pseudo_exec(child); - } - if (outpipe[1] != -1) { - close(outpipe[1]); - } - - /* put our child in the process group whose leader is the - first process in this pipe */ - setpgid(child->pid, newjob->progs[0].pid); - if (nextin != 0) - close(nextin); - if (nextout != 1) - close(nextout); - - /* If there isn't another process, nextin is garbage - but it doesn't matter */ - nextin = pipefds[0]; - } - - newjob->pgrp = newjob->progs[0].pid; - - insert_job(newjob, inbg); - - return 0; -} - -static int busy_loop(FILE * input) -{ - char *command; - char *next_command = NULL; - struct job newjob; - int i; - int inbg = 0; - int status; -#if ENABLE_LASH_JOB_CONTROL - pid_t parent_pgrp; - /* save current owner of TTY so we can restore it on exit */ - parent_pgrp = tcgetpgrp(shell_terminal); -#endif - newjob.job_list = &job_list; - newjob.job_context = DEFAULT_CONTEXT; - - command = xzalloc(BUFSIZ); - - while (1) { - if (!job_list.fg) { - /* no job is in the foreground */ - - /* see if any background processes have exited */ - checkjobs(&job_list); - - if (!next_command) { - if (get_command_bufsiz(input, command)) - break; - next_command = command; - } - - if (!expand_arguments(next_command)) { - free(command); - command = xzalloc(BUFSIZ); - next_command = NULL; - continue; - } - - if (!parse_command(&next_command, &newjob, &inbg) && - newjob.num_progs) { - int pipefds[2] = { -1, -1 }; - debug_printf("job=%p fed to run_command by busy_loop()'\n", - &newjob); - run_command(&newjob, inbg, pipefds); - } - else { - free(command); - command = xzalloc(BUFSIZ); - next_command = NULL; - } - } else { - /* a job is running in the foreground; wait for it */ - i = 0; - while (!job_list.fg->progs[i].pid || - job_list.fg->progs[i].is_stopped == 1) i++; - - if (waitpid(job_list.fg->progs[i].pid, &status, WUNTRACED) < 0) { - if (errno != ECHILD) { - bb_perror_msg_and_die("waitpid(%d)", job_list.fg->progs[i].pid); - } - } - - if (WIFEXITED(status) || WIFSIGNALED(status)) { - /* the child exited */ - job_list.fg->running_progs--; - job_list.fg->progs[i].pid = 0; - - last_return_code = WEXITSTATUS(status); - - if (!job_list.fg->running_progs) { - /* child exited */ - remove_job(&job_list, job_list.fg); - job_list.fg = NULL; - } - } -#if ENABLE_LASH_JOB_CONTROL - else { - /* the child was stopped */ - job_list.fg->stopped_progs++; - job_list.fg->progs[i].is_stopped = 1; - - if (job_list.fg->stopped_progs == job_list.fg->running_progs) { - printf("\n" JOB_STATUS_FORMAT, job_list.fg->jobid, - "Stopped", job_list.fg->text); - job_list.fg = NULL; - } - } - - if (!job_list.fg) { - /* move the shell to the foreground */ - /* suppress messages when run from /linuxrc mag@sysgo.de */ - if (tcsetpgrp(shell_terminal, getpgrp()) && errno != ENOTTY) - bb_perror_msg("tcsetpgrp"); - } -#endif - } - } - free(command); - -#if ENABLE_LASH_JOB_CONTROL - /* return controlling TTY back to parent process group before exiting */ - if (tcsetpgrp(shell_terminal, parent_pgrp) && errno != ENOTTY) - bb_perror_msg("tcsetpgrp"); -#endif - - /* return exit status if called with "-c" */ - if (input == NULL && WIFEXITED(status)) - return WEXITSTATUS(status); - - return 0; -} - -#if ENABLE_FEATURE_CLEAN_UP -static void free_memory(void) -{ - free(cwd); - - if (job_list.fg && !job_list.fg->running_progs) { - remove_job(&job_list, job_list.fg); - } -} -#else -void free_memory(void); -#endif - -#if ENABLE_LASH_JOB_CONTROL -/* Make sure we have a controlling tty. If we get started under a job - * aware app (like bash for example), make sure we are now in charge so - * we don't fight over who gets the foreground */ -static void setup_job_control(void) -{ - int status; - pid_t shell_pgrp; - - /* Loop until we are in the foreground. */ - while ((status = tcgetpgrp(shell_terminal)) >= 0) { - shell_pgrp = getpgrp(); - if (status == shell_pgrp) { - break; - } - kill(- shell_pgrp, SIGTTIN); - } - - /* Ignore interactive and job-control signals. */ - signal(SIGINT, SIG_IGN); - signal(SIGQUIT, SIG_IGN); - signal(SIGTSTP, SIG_IGN); - signal(SIGTTIN, SIG_IGN); - signal(SIGTTOU, SIG_IGN); - signal(SIGCHLD, SIG_IGN); - - /* Put ourselves in our own process group. */ - setsid(); - shell_pgrp = getpid(); - setpgid(shell_pgrp, shell_pgrp); - - /* Grab control of the terminal. */ - tcsetpgrp(shell_terminal, shell_pgrp); -} -#else -static inline void setup_job_control(void) -{ -} -#endif - -int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; -int lash_main(int argc, char **argv) -{ - unsigned opt; - FILE *input = stdin; - - global_argc = argc; - global_argv = argv; - -#if ENABLE_FEATURE_EDITING - line_input_state = new_line_input_t(FOR_SHELL); -#endif - - /* These variables need re-initializing when recursing */ - last_jobid = 0; - close_me_list = NULL; - job_list.head = NULL; - job_list.fg = NULL; - last_return_code = 1; - - if (global_argv[0] && global_argv[0][0] == '-') { - FILE *prof_input; - prof_input = fopen("/etc/profile", "r"); - if (prof_input) { - llist_add_to(&close_me_list, (void *)(long)fileno(prof_input)); - /* Now run the file */ - busy_loop(prof_input); - fclose_if_not_stdin(prof_input); - llist_pop(&close_me_list); - } - } - - opt = getopt32(argv, "+ic:", &local_pending_command); -#define LASH_OPT_i (1<<0) -#define LASH_OPT_c (1<<1) - if (opt & LASH_OPT_c) { - input = NULL; - optind++; - global_argv += optind; - } - /* A shell is interactive if the `-i' flag was given, or if all of - * the following conditions are met: - * no -c command - * no arguments remaining or the -s flag given - * standard input is a terminal - * standard output is a terminal - * Refer to Posix.2, the description of the `sh' utility. */ - if (global_argv[optind] == NULL && input == stdin - && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO) - ) { - opt |= LASH_OPT_i; - } - setup_job_control(); - if (opt & LASH_OPT_i) { - /* Looks like they want an interactive shell */ - if (!ENABLE_FEATURE_SH_EXTRA_QUIET) { - printf("\n\n%s built-in shell (lash)\n" - "Enter 'help' for a list of built-in commands.\n\n", - bb_banner); - } - } else if (!local_pending_command && global_argv[optind]) { - //printf( "optind=%d argv[optind]='%s'\n", optind, argv[optind]); - input = xfopen(global_argv[optind], "r"); - /* be lazy, never mark this closed */ - llist_add_to(&close_me_list, (void *)(long)fileno(input)); - } - - /* initialize the cwd -- this is never freed...*/ - update_cwd(); - - if (ENABLE_FEATURE_CLEAN_UP) atexit(free_memory); - - if (ENABLE_FEATURE_EDITING) cmdedit_set_initial_prompt(); - else PS1 = NULL; - - return busy_loop(input); -} diff --git a/shell/lash_unused.c b/shell/lash_unused.c new file mode 100644 index 000000000..781dfdb5a --- /dev/null +++ b/shell/lash_unused.c @@ -0,0 +1,1570 @@ +/* vi: set sw=4 ts=4: */ +/* + * lash -- the BusyBox Lame-Ass SHell + * + * Copyright (C) 1999-2004 by Erik Andersen + * + * Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is + * under the following liberal license: "We have placed this source code in the + * public domain. Use it in any project, free or commercial." + * + * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. + */ + +/* This shell's parsing engine is officially at a dead-end. Future + * work shell work should be done using hush, msh, or ash. This is + * still a very useful, small shell -- it just don't need any more + * features beyond what it already has... + */ + +//For debugging/development on the shell only... +//#define DEBUG_SHELL + +#include +#include + +#include "busybox.h" /* for struct bb_applet */ + +#define expand_t glob_t + +/* Always enable for the moment... */ +#define CONFIG_LASH_PIPE_N_REDIRECTS +#define CONFIG_LASH_JOB_CONTROL +#define ENABLE_LASH_PIPE_N_REDIRECTS 1 +#define ENABLE_LASH_JOB_CONTROL 1 + + +enum { MAX_READ = 128 }; /* size of input buffer for 'read' builtin */ +#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" + + +#if ENABLE_LASH_PIPE_N_REDIRECTS +enum redir_type { REDIRECT_INPUT, REDIRECT_OVERWRITE, + REDIRECT_APPEND +}; +#endif + +enum { + DEFAULT_CONTEXT = 0x1, + IF_TRUE_CONTEXT = 0x2, + IF_FALSE_CONTEXT = 0x4, + THEN_EXP_CONTEXT = 0x8, + ELSE_EXP_CONTEXT = 0x10 +}; + +#define LASH_OPT_DONE (1) +#define LASH_OPT_SAW_QUOTE (2) + +#if ENABLE_LASH_PIPE_N_REDIRECTS +struct redir_struct { + enum redir_type type; /* type of redirection */ + int fd; /* file descriptor being redirected */ + char *filename; /* file to redirect fd to */ +}; +#endif + +struct child_prog { + pid_t pid; /* 0 if exited */ + char **argv; /* program name and arguments */ + int num_redirects; /* elements in redirection array */ + int is_stopped; /* is the program currently running? */ + struct job *family; /* pointer back to the child's parent job */ +#if ENABLE_LASH_PIPE_N_REDIRECTS + struct redir_struct *redirects; /* I/O redirects */ +#endif +}; + +struct jobset { + struct job *head; /* head of list of running jobs */ + struct job *fg; /* current foreground job */ +}; + +struct job { + int jobid; /* job number */ + int num_progs; /* total number of programs in job */ + int running_progs; /* number of programs running */ + char *text; /* name of job */ + char *cmdbuf; /* buffer various argv's point into */ + pid_t pgrp; /* process group ID for the job */ + struct child_prog *progs; /* array of programs in job */ + struct job *next; /* to track background commands */ + int stopped_progs; /* number of programs alive, but stopped */ + unsigned int job_context; /* bitmask defining current context */ + struct jobset *job_list; +}; + +struct built_in_command { + const char *cmd; /* name */ + const char *descr; /* description */ + int (*function) (struct child_prog *); /* function ptr */ +}; + +/* function prototypes for builtins */ +static int builtin_cd(struct child_prog *cmd); +static int builtin_exec(struct child_prog *cmd); +static int builtin_exit(struct child_prog *cmd); +static int builtin_fg_bg(struct child_prog *cmd); +static int builtin_help(struct child_prog *cmd); +static int builtin_jobs(struct child_prog *dummy); +static int builtin_pwd(struct child_prog *dummy); +static int builtin_export(struct child_prog *cmd); +static int builtin_source(struct child_prog *cmd); +static int builtin_unset(struct child_prog *cmd); +static int builtin_read(struct child_prog *cmd); + + +/* function prototypes for shell stuff */ +static void checkjobs(struct jobset *job_list); +static void remove_job(struct jobset *j_list, struct job *job); +static int get_command_bufsiz(FILE * source, char *command); +static int parse_command(char **command_ptr, struct job *job, int *inbg); +static int run_command(struct job *newjob, int inbg, int outpipe[2]); +static int pseudo_exec(struct child_prog *cmd) ATTRIBUTE_NORETURN; +static int busy_loop(FILE * input); + + +/* Table of built-in functions (these are non-forking builtins, meaning they + * can change global variables in the parent shell process but they will not + * work with pipes and redirects; 'unset foo | whatever' will not work) */ +static const struct built_in_command bltins[] = { + {"bg" , "Resume a job in the background", builtin_fg_bg}, + {"cd" , "Change working directory", builtin_cd}, + {"exec" , "Exec command, replacing this shell with the exec'd process", builtin_exec}, + {"exit" , "Exit from shell()", builtin_exit}, + {"fg" , "Bring job into the foreground", builtin_fg_bg}, + {"jobs" , "Lists the active jobs", builtin_jobs}, + {"export", "Set environment variable", builtin_export}, + {"unset" , "Unset environment variable", builtin_unset}, + {"read" , "Input environment variable", builtin_read}, + {"." , "Source-in and run commands in a file", builtin_source}, + /* These were "forked applets", but distinction was nuked */ + /* Original comment retained: */ + /* Table of forking built-in functions (things that fork cannot change global + * variables in the parent process, such as the current working directory) */ + {"pwd" , "Print current directory", builtin_pwd}, + {"help" , "List shell built-in commands", builtin_help}, + /* to do: add ulimit */ +}; + + +#define VEC_LAST(v) v[ARRAY_SIZE(v)-1] + + +static int shell_context; /* Type prompt trigger (PS1 or PS2) */ + + +/* Globals that are static to this file */ +static char *cwd; +static char *local_pending_command; +static struct jobset job_list = { NULL, NULL }; +static int global_argc; +static char **global_argv; +static llist_t *close_me_list; +static int last_return_code; +static int last_bg_pid; +static unsigned int last_jobid; +static int shell_terminal; +static const char *PS1; +static const char *PS2 = "> "; + + +#ifdef DEBUG_SHELL +static inline void debug_printf(const char *format, ...) +{ + va_list args; + va_start(args, format); + vfprintf(stderr, format, args); + va_end(args); +} +#else +static inline void debug_printf(const char ATTRIBUTE_UNUSED *format, ...) { } +#endif + +/* + Most builtins need access to the struct child_prog that has + their arguments, previously coded as cmd->progs[0]. That coding + can exhibit a bug, if the builtin is not the first command in + a pipeline: "echo foo | exec sort" will attempt to exec foo. + +builtin previous use notes +------ ----------------- --------- +cd cmd->progs[0] +exec cmd->progs[0] squashed bug: didn't look for applets or forking builtins +exit cmd->progs[0] +fg_bg cmd->progs[0], job_list->head, job_list->fg +help 0 +jobs job_list->head +pwd 0 +export cmd->progs[0] +source cmd->progs[0] +unset cmd->progs[0] +read cmd->progs[0] + +I added "struct job *family;" to struct child_prog, +and switched API to builtin_foo(struct child_prog *child); +So cmd->text becomes child->family->text + cmd->job_context becomes child->family->job_context + cmd->progs[0] becomes *child + job_list becomes child->family->job_list + */ + + +static void update_cwd(void) +{ + cwd = xrealloc_getcwd_or_warn(cwd); + if (!cwd) + cwd = xstrdup(bb_msg_unknown); +} + +/* built-in 'cd ' handler */ +static int builtin_cd(struct child_prog *child) +{ + char *newdir; + + if (child->argv[1] == NULL) + newdir = getenv("HOME"); + else + newdir = child->argv[1]; + if (chdir(newdir)) { + bb_perror_msg("cd: %s", newdir); + return EXIT_FAILURE; + } + update_cwd(); + return EXIT_SUCCESS; +} + +/* built-in 'exec' handler */ +static int builtin_exec(struct child_prog *child) +{ + if (child->argv[1] == NULL) + return EXIT_SUCCESS; /* Really? */ + child->argv++; + while (close_me_list) + close((long)llist_pop(&close_me_list)); + pseudo_exec(child); + /* never returns */ +} + +/* built-in 'exit' handler */ +static int builtin_exit(struct child_prog *child) +{ + if (child->argv[1] == NULL) + exit(EXIT_SUCCESS); + + exit(atoi(child->argv[1])); +} + +/* built-in 'fg' and 'bg' handler */ +static int builtin_fg_bg(struct child_prog *child) +{ + int i, jobnum; + struct job *job; + + /* If they gave us no args, assume they want the last backgrounded task */ + if (!child->argv[1]) { + for (job = child->family->job_list->head; job; job = job->next) { + if (job->jobid == last_jobid) { + goto found; + } + } + bb_error_msg("%s: no current job", child->argv[0]); + return EXIT_FAILURE; + } + if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) { + bb_error_msg(bb_msg_invalid_arg, child->argv[1], child->argv[0]); + return EXIT_FAILURE; + } + for (job = child->family->job_list->head; job; job = job->next) { + if (job->jobid == jobnum) { + goto found; + } + } + bb_error_msg("%s: %d: no such job", child->argv[0], jobnum); + return EXIT_FAILURE; + found: + if (*child->argv[0] == 'f') { + /* Put the job into the foreground. */ + tcsetpgrp(shell_terminal, job->pgrp); + + child->family->job_list->fg = job; + } + + /* Restart the processes in the job */ + for (i = 0; i < job->num_progs; i++) + job->progs[i].is_stopped = 0; + + job->stopped_progs = 0; + + i = kill(- job->pgrp, SIGCONT); + if (i < 0) { + if (errno == ESRCH) { + remove_job(&job_list, job); + } else { + bb_perror_msg("kill (SIGCONT)"); + } + } + + return EXIT_SUCCESS; +} + +/* built-in 'help' handler */ +static int builtin_help(struct child_prog ATTRIBUTE_UNUSED *dummy) +{ + const struct built_in_command *x; + + printf("\nBuilt-in commands:\n" + "-------------------\n"); + for (x = bltins; x <= &VEC_LAST(bltins); x++) { + if (x->descr == NULL) + continue; + printf("%s\t%s\n", x->cmd, x->descr); + } + bb_putchar('\n'); + return EXIT_SUCCESS; +} + +/* built-in 'jobs' handler */ +static int builtin_jobs(struct child_prog *child) +{ + struct job *job; + const char *status_string; + + for (job = child->family->job_list->head; job; job = job->next) { + if (job->running_progs == job->stopped_progs) + status_string = "Stopped"; + else + status_string = "Running"; + + printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text); + } + return EXIT_SUCCESS; +} + + +/* built-in 'pwd' handler */ +static int builtin_pwd(struct child_prog ATTRIBUTE_UNUSED *dummy) +{ + update_cwd(); + puts(cwd); + return EXIT_SUCCESS; +} + +/* built-in 'export VAR=value' handler */ +static int builtin_export(struct child_prog *child) +{ + int res; + char *v = child->argv[1]; + + if (v == NULL) { + char **e; + for (e = environ; *e; e++) { + puts(*e); + } + return 0; + } + res = putenv(v); + if (res) + bb_perror_msg("export"); +#if ENABLE_FEATURE_EDITING_FANCY_PROMPT + if (strncmp(v, "PS1=", 4) == 0) + PS1 = getenv("PS1"); +#endif + +#if ENABLE_LOCALE_SUPPORT + // TODO: why getenv? "" would be just as good... + if (strncmp(v, "LC_ALL=", 7) == 0) + setlocale(LC_ALL, getenv("LC_ALL")); + if (strncmp(v, "LC_CTYPE=", 9) == 0) + setlocale(LC_CTYPE, getenv("LC_CTYPE")); +#endif + + return res; +} + +/* built-in 'read VAR' handler */ +static int builtin_read(struct child_prog *child) +{ + int res = 0, len; + char *s; + char string[MAX_READ]; + + if (child->argv[1]) { + /* argument (VAR) given: put "VAR=" into buffer */ + safe_strncpy(string, child->argv[1], MAX_READ-1); + len = strlen(string); + string[len++] = '='; + string[len] = '\0'; + fgets(&string[len], sizeof(string) - len, stdin); /* read string */ + res = strlen(string); + if (res > len) + string[--res] = '\0'; /* chomp trailing newline */ + /* + ** string should now contain "VAR=" + ** copy it (putenv() won't do that, so we must make sure + ** the string resides in a static buffer!) + */ + res = -1; + s = strdup(string); + if (s) + res = putenv(s); + if (res) + bb_perror_msg("read"); + } else + fgets(string, sizeof(string), stdin); + + return res; +} + +/* Built-in '.' handler (read-in and execute commands from file) */ +static int builtin_source(struct child_prog *child) +{ + FILE *input; + int status; + + input = fopen_or_warn(child->argv[1], "r"); + if (!input) { + return EXIT_FAILURE; + } + + llist_add_to(&close_me_list, (void *)(long)fileno(input)); + /* Now run the file */ + status = busy_loop(input); + fclose(input); + llist_pop(&close_me_list); + return status; +} + +/* built-in 'unset VAR' handler */ +static int builtin_unset(struct child_prog *child) +{ + if (child->argv[1] == NULL) { + printf(bb_msg_requires_arg, "unset"); + return EXIT_FAILURE; + } + unsetenv(child->argv[1]); + return EXIT_SUCCESS; +} + +#if ENABLE_LASH_JOB_CONTROL +/* free up all memory from a job */ +static void free_job(struct job *cmd) +{ + int i; + struct jobset *keep; + + for (i = 0; i < cmd->num_progs; i++) { + free(cmd->progs[i].argv); +#if ENABLE_LASH_PIPE_N_REDIRECTS + free(cmd->progs[i].redirects); +#endif + } + free(cmd->progs); + free(cmd->text); + free(cmd->cmdbuf); + keep = cmd->job_list; + memset(cmd, 0, sizeof(struct job)); + cmd->job_list = keep; +} + +/* remove a job from a jobset */ +static void remove_job(struct jobset *j_list, struct job *job) +{ + struct job *prevjob; + + free_job(job); + if (job == j_list->head) { + j_list->head = job->next; + } else { + prevjob = j_list->head; + while (prevjob->next != job) + prevjob = prevjob->next; + prevjob->next = job->next; + } + + if (j_list->head) + last_jobid = j_list->head->jobid; + else + last_jobid = 0; + + free(job); +} + +/* Checks to see if any background processes have exited -- if they + have, figure out why and see if a job has completed */ +static void checkjobs(struct jobset *j_list) +{ + struct job *job; + pid_t childpid; + int status; + int prognum = 0; + + while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) { + for (job = j_list->head; job; job = job->next) { + prognum = 0; + while (prognum < job->num_progs && + job->progs[prognum].pid != childpid) prognum++; + if (prognum < job->num_progs) + break; + } + + /* This happens on backticked commands */ + if (job == NULL) + return; + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* child exited */ + job->running_progs--; + job->progs[prognum].pid = 0; + + if (!job->running_progs) { + printf(JOB_STATUS_FORMAT, job->jobid, "Done", job->text); + last_jobid = 0; + remove_job(j_list, job); + } + } else { + /* child stopped */ + job->stopped_progs++; + job->progs[prognum].is_stopped = 1; + } + } + + if (childpid == -1 && errno != ECHILD) + bb_perror_msg("waitpid"); +} +#else +static void checkjobs(struct jobset *j_list) +{ +} +static void free_job(struct job *cmd) +{ +} +static void remove_job(struct jobset *j_list, struct job *job) +{ +} +#endif + +#if ENABLE_LASH_PIPE_N_REDIRECTS +/* squirrel != NULL means we squirrel away copies of stdin, stdout, + * and stderr if they are redirected. */ +static int setup_redirects(struct child_prog *prog, int squirrel[]) +{ + int i; + int openfd; + int mode = O_RDONLY; + struct redir_struct *redir = prog->redirects; + + for (i = 0; i < prog->num_redirects; i++, redir++) { + switch (redir->type) { + case REDIRECT_INPUT: + mode = O_RDONLY; + break; + case REDIRECT_OVERWRITE: + mode = O_WRONLY | O_CREAT | O_TRUNC; + break; + case REDIRECT_APPEND: + mode = O_WRONLY | O_CREAT | O_APPEND; + break; + } + + openfd = open3_or_warn(redir->filename, mode, 0666); + if (openfd < 0) { + /* this could get lost if stderr has been redirected, but + bash and ash both lose it as well (though zsh doesn't!) */ + return 1; + } + + if (openfd != redir->fd) { + if (squirrel && redir->fd < 3) { + squirrel[redir->fd] = dup(redir->fd); + close_on_exec_on(squirrel[redir->fd]); + } + dup2(openfd, redir->fd); + close(openfd); + } + } + + return 0; +} + +static void restore_redirects(int squirrel[]) +{ + int i, fd; + for (i = 0; i < 3; i++) { + fd = squirrel[i]; + if (fd != -1) { + /* No error checking. I sure wouldn't know what + * to do with an error if I found one! */ + dup2(fd, i); + close(fd); + } + } +} +#else +static inline int setup_redirects(struct child_prog *prog, int squirrel[]) +{ + return 0; +} +static inline void restore_redirects(int squirrel[]) +{ +} +#endif + +static inline void cmdedit_set_initial_prompt(void) +{ +#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT + PS1 = NULL; +#else + PS1 = getenv("PS1"); + if (PS1 == 0) + PS1 = "\\w \\$ "; +#endif +} + +static inline const char* setup_prompt_string(void) +{ +#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT + /* Set up the prompt */ + if (shell_context == 0) { + char *ns; + free((char*)PS1); + ns = xmalloc(strlen(cwd)+4); + sprintf(ns, "%s %c ", cwd, (geteuid() != 0) ? '$': '#'); + PS1 = ns; + return ns; + } else { + return PS2; + } +#else + return (shell_context == 0)? PS1 : PS2; +#endif +} + +#if ENABLE_FEATURE_EDITING +static line_input_t *line_input_state; +#endif + +static int get_command_bufsiz(FILE * source, char *command) +{ + const char *prompt_str; + + if (source == NULL) { + if (local_pending_command) { + /* a command specified (-c option): return it & mark it done */ + strncpy(command, local_pending_command, BUFSIZ); + local_pending_command = NULL; + return 0; + } + return 1; + } + + if (source == stdin) { + prompt_str = setup_prompt_string(); + +#if ENABLE_FEATURE_EDITING + /* + ** enable command line editing only while a command line + ** is actually being read; otherwise, we'll end up bequeathing + ** atexit() handlers and other unwanted stuff to our + ** child processes (rob@sysgo.de) + */ + read_line_input(prompt_str, command, BUFSIZ, line_input_state); + return 0; +#else + fputs(prompt_str, stdout); +#endif + } + + if (!fgets(command, BUFSIZ - 2, source)) { + if (source == stdin) + bb_putchar('\n'); + return 1; + } + + return 0; +} + +static char * strsep_space(char *string, int * ix) +{ + /* Short circuit the trivial case */ + if (!string || ! string[*ix]) + return NULL; + + /* Find the end of the token. */ + while (string[*ix] && !isspace(string[*ix]) ) { + (*ix)++; + } + + /* Find the end of any whitespace trailing behind + * the token and let that be part of the token */ + while (string[*ix] && (isspace)(string[*ix]) ) { + (*ix)++; + } + + if (!*ix) { + /* Nothing useful was found */ + return NULL; + } + + return xstrndup(string, *ix); +} + +static int expand_arguments(char *command) +{ + static const char out_of_space[] ALIGN1 = "out of space during expansion"; + + int total_length = 0, length, i, retval, ix = 0; + expand_t expand_result; + char *tmpcmd, *cmd, *cmd_copy; + char *src, *dst, *var; + int flags = GLOB_NOCHECK +#ifdef GLOB_BRACE + | GLOB_BRACE +#endif +#ifdef GLOB_TILDE + | GLOB_TILDE +#endif + ; + + /* get rid of the terminating \n */ + chomp(command); + + /* Fix up escape sequences to be the Real Thing(tm) */ + while (command && command[ix]) { + if (command[ix] == '\\') { + const char *tmp = command+ix+1; + command[ix] = bb_process_escape_sequence( &tmp ); + memmove(command+ix + 1, tmp, strlen(tmp)+1); + } + ix++; + } + /* Use glob and then fixup environment variables and such */ + + /* It turns out that glob is very stupid. We have to feed it one word at a + * time since it can't cope with a full string. Here we convert command + * (char*) into cmd (char**, one word per string) */ + + /* We need a clean copy, so strsep can mess up the copy while + * we write stuff into the original (in a minute) */ + cmd = cmd_copy = xstrdup(command); + *command = '\0'; + for (ix = 0, tmpcmd = cmd; + (tmpcmd = strsep_space(cmd, &ix)) != NULL; cmd += ix, ix = 0) { + if (*tmpcmd == '\0') + break; + /* we need to trim() the result for glob! */ + trim(tmpcmd); + retval = glob(tmpcmd, flags, NULL, &expand_result); + free(tmpcmd); /* Free mem allocated by strsep_space */ + if (retval == GLOB_NOSPACE) { + /* Mem may have been allocated... */ + globfree(&expand_result); + bb_error_msg(out_of_space); + return FALSE; + } else if (retval != 0) { + /* Some other error. GLOB_NOMATCH shouldn't + * happen because of the GLOB_NOCHECK flag in + * the glob call. */ + bb_error_msg("syntax error"); + return FALSE; + } else { + /* Convert from char** (one word per string) to a simple char*, + * but don't overflow command which is BUFSIZ in length */ + for (i = 0; i < expand_result.gl_pathc; i++) { + length = strlen(expand_result.gl_pathv[i]); + if (total_length+length+1 >= BUFSIZ) { + bb_error_msg(out_of_space); + return FALSE; + } + strcat(command+total_length, " "); + total_length += 1; + strcat(command+total_length, expand_result.gl_pathv[i]); + total_length += length; + } + globfree(&expand_result); + } + } + free(cmd_copy); + trim(command); + + /* Now do the shell variable substitutions which + * wordexp can't do for us, namely $? and $! */ + src = command; + while ((dst = strchr(src,'$')) != NULL) { + var = NULL; + switch (*(dst+1)) { + case '?': + var = itoa(last_return_code); + break; + case '!': + if (last_bg_pid == -1) + *var = '\0'; + else + var = itoa(last_bg_pid); + break; + /* Everything else like $$, $#, $[0-9], etc. should all be + * expanded by wordexp(), so we can in theory skip that stuff + * here, but just to be on the safe side (i.e., since uClibc + * wordexp doesn't do this stuff yet), lets leave it in for + * now. */ + case '$': + var = itoa(getpid()); + break; + case '#': + var = itoa(global_argc - 1); + break; + case '0':case '1':case '2':case '3':case '4': + case '5':case '6':case '7':case '8':case '9': + { + int ixx = *(dst+1)-48+1; + if (ixx >= global_argc) { + var = '\0'; + } else { + var = global_argv[ixx]; + } + } + break; + + } + if (var) { + /* a single character construction was found, and + * already handled in the case statement */ + src = dst + 2; + } else { + /* Looks like an environment variable */ + char delim_hold; + int num_skip_chars = 0; + int dstlen = strlen(dst); + /* Is this a ${foo} type variable? */ + if (dstlen >= 2 && *(dst+1) == '{') { + src = strchr(dst+1, '}'); + num_skip_chars = 1; + } else { + src = dst + 1; + while ((isalnum)(*src) || *src == '_') src++; + } + if (src == NULL) { + src = dst+dstlen; + } + delim_hold = *src; + *src = '\0'; /* temporary */ + var = getenv(dst + 1 + num_skip_chars); + *src = delim_hold; + src += num_skip_chars; + } + if (var == NULL) { + /* Seems we got an un-expandable variable. So delete it. */ + var = (char*)""; + } + { + int subst_len = strlen(var); + int trail_len = strlen(src); + if (dst+subst_len+trail_len >= command+BUFSIZ) { + bb_error_msg(out_of_space); + return FALSE; + } + /* Move stuff to the end of the string to accommodate + * filling the created gap with the new stuff */ + memmove(dst+subst_len, src, trail_len+1); + /* Now copy in the new stuff */ + memcpy(dst, var, subst_len); + src = dst+subst_len; + } + } + + return TRUE; +} + +/* Return cmd->num_progs as 0 if no command is present (e.g. an empty + line). If a valid command is found, command_ptr is set to point to + the beginning of the next command (if the original command had more + then one job associated with it) or NULL if no more commands are + present. */ +static int parse_command(char **command_ptr, struct job *job, int *inbg) +{ + char *command; + char *return_command = NULL; + char *src, *buf; + int argc_l; + int flag; + int argv_alloced; + char quote = '\0'; + struct child_prog *prog; +#if ENABLE_LASH_PIPE_N_REDIRECTS + int i; + char *chptr; +#endif + + /* skip leading white space */ + *command_ptr = skip_whitespace(*command_ptr); + + /* this handles empty lines or leading '#' characters */ + if (!**command_ptr || (**command_ptr == '#')) { + job->num_progs = 0; + return 0; + } + + *inbg = 0; + job->num_progs = 1; + job->progs = xmalloc(sizeof(*job->progs)); + + /* We set the argv elements to point inside of this string. The + memory is freed by free_job(). Allocate twice the original + length in case we need to quote every single character. + + Getting clean memory relieves us of the task of NULL + terminating things and makes the rest of this look a bit + cleaner (though it is, admittedly, a tad less efficient) */ + job->cmdbuf = command = xzalloc(2*strlen(*command_ptr) + 1); + job->text = NULL; + + prog = job->progs; + prog->num_redirects = 0; + prog->is_stopped = 0; + prog->family = job; +#if ENABLE_LASH_PIPE_N_REDIRECTS + prog->redirects = NULL; +#endif + + argv_alloced = 5; + prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced); + prog->argv[0] = job->cmdbuf; + + flag = argc_l = 0; + buf = command; + src = *command_ptr; + while (*src && !(flag & LASH_OPT_DONE)) { + if (quote == *src) { + quote = '\0'; + } else if (quote) { + if (*src == '\\') { + src++; + if (!*src) { + bb_error_msg("character expected after \\"); + free_job(job); + return 1; + } + + /* in shell, "\'" should yield \' */ + if (*src != quote) { + *buf++ = '\\'; + *buf++ = '\\'; + } + } else if (*src == '*' || *src == '?' || *src == '[' || + *src == ']') *buf++ = '\\'; + *buf++ = *src; + } else if (isspace(*src)) { + if (*prog->argv[argc_l] || (flag & LASH_OPT_SAW_QUOTE)) { + buf++, argc_l++; + /* +1 here leaves room for the NULL which ends argv */ + if ((argc_l + 1) == argv_alloced) { + argv_alloced += 5; + prog->argv = xrealloc(prog->argv, + sizeof(*prog->argv) * argv_alloced); + } + prog->argv[argc_l] = buf; + flag ^= LASH_OPT_SAW_QUOTE; + } + } else + switch (*src) { + case '"': + case '\'': + quote = *src; + flag |= LASH_OPT_SAW_QUOTE; + break; + + case '#': /* comment */ + if (*(src-1)== '$') + *buf++ = *src; + else + flag |= LASH_OPT_DONE; + break; + +#if ENABLE_LASH_PIPE_N_REDIRECTS + case '>': /* redirects */ + case '<': + i = prog->num_redirects++; + prog->redirects = xrealloc(prog->redirects, + sizeof(*prog->redirects) * (i + 1)); + + prog->redirects[i].fd = -1; + if (buf != prog->argv[argc_l]) { + /* the stuff before this character may be the file number + being redirected */ + prog->redirects[i].fd = + strtol(prog->argv[argc_l], &chptr, 10); + + if (*chptr && *prog->argv[argc_l]) { + buf++, argc_l++; + prog->argv[argc_l] = buf; + } + } + + if (prog->redirects[i].fd == -1) { + if (*src == '>') + prog->redirects[i].fd = 1; + else + prog->redirects[i].fd = 0; + } + + if (*src++ == '>') { + if (*src == '>') + prog->redirects[i].type = + REDIRECT_APPEND, src++; + else + prog->redirects[i].type = REDIRECT_OVERWRITE; + } else { + prog->redirects[i].type = REDIRECT_INPUT; + } + + /* This isn't POSIX sh compliant. Oh well. */ + chptr = src; + chptr = skip_whitespace(chptr); + + if (!*chptr) { + bb_error_msg("file name expected after %c", *(src-1)); + free_job(job); + job->num_progs = 0; + return 1; + } + + prog->redirects[i].filename = buf; + while (*chptr && !isspace(*chptr)) + *buf++ = *chptr++; + + src = chptr - 1; /* we src++ later */ + prog->argv[argc_l] = ++buf; + break; + + case '|': /* pipe */ + /* finish this command */ + if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE) + argc_l++; + if (!argc_l) { + goto empty_command_in_pipe; + } + prog->argv[argc_l] = NULL; + + /* and start the next */ + job->num_progs++; + job->progs = xrealloc(job->progs, + sizeof(*job->progs) * job->num_progs); + prog = job->progs + (job->num_progs - 1); + prog->num_redirects = 0; + prog->redirects = NULL; + prog->is_stopped = 0; + prog->family = job; + argc_l = 0; + + argv_alloced = 5; + prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced); + prog->argv[0] = ++buf; + + src++; + src = skip_whitespace(src); + + if (!*src) { +empty_command_in_pipe: + bb_error_msg("empty command in pipe"); + free_job(job); + job->num_progs = 0; + return 1; + } + src--; /* we'll ++ it at the end of the loop */ + + break; +#endif + +#if ENABLE_LASH_JOB_CONTROL + case '&': /* background */ + *inbg = 1; + /* fallthrough */ +#endif + case ';': /* multiple commands */ + flag |= LASH_OPT_DONE; + return_command = *command_ptr + (src - *command_ptr) + 1; + break; + + case '\\': + src++; + if (!*src) { + bb_error_msg("character expected after \\"); + free_job(job); + return 1; + } + if (*src == '*' || *src == '[' || *src == ']' + || *src == '?') *buf++ = '\\'; + /* fallthrough */ + default: + *buf++ = *src; + } + + src++; + } + + if (*prog->argv[argc_l] || flag & LASH_OPT_SAW_QUOTE) { + argc_l++; + } + if (!argc_l) { + free_job(job); + return 0; + } + prog->argv[argc_l] = NULL; + + if (!return_command) { + job->text = xstrdup(*command_ptr); + } else { + /* This leaves any trailing spaces, which is a bit sloppy */ + job->text = xstrndup(*command_ptr, return_command - *command_ptr); + } + + *command_ptr = return_command; + + return 0; +} + +/* Run the child_prog, no matter what kind of command it uses. + */ +static int pseudo_exec(struct child_prog *child) +{ + const struct built_in_command *x; + + /* Check if the command matches any of the non-forking builtins. + * Depending on context, this might be redundant. But it's + * easier to waste a few CPU cycles than it is to figure out + * if this is one of those cases. + */ + /* Check if the command matches any of the forking builtins. */ + for (x = bltins; x <= &VEC_LAST(bltins); x++) { + if (strcmp(child->argv[0], x->cmd) == 0) { + _exit(x->function(child)); + } + } + + /* Check if the command matches any busybox internal + * commands ("applets") here. Following discussions from + * November 2000 on busybox@busybox.net, don't use + * bb_get_last_path_component_nostrip(). This way explicit + * (with slashes) filenames will never be interpreted as an + * applet, just like with builtins. This way the user can + * override an applet with an explicit filename reference. + * The only downside to this change is that an explicit + * /bin/foo invocation will fork and exec /bin/foo, even if + * /bin/foo is a symlink to busybox. + */ + if (ENABLE_FEATURE_SH_STANDALONE) { + run_applet_and_exit(child->argv[0], child->argv); + } + + execvp(child->argv[0], child->argv); + + /* Do not use bb_perror_msg_and_die() here, since we must not + * call exit() but should call _exit() instead */ + bb_simple_perror_msg(child->argv[0]); + _exit(EXIT_FAILURE); +} + +static void insert_job(struct job *newjob, int inbg) +{ + struct job *thejob; + struct jobset *j_list = newjob->job_list; + + /* find the ID for thejob to use */ + newjob->jobid = 1; + for (thejob = j_list->head; thejob; thejob = thejob->next) + if (thejob->jobid >= newjob->jobid) + newjob->jobid = thejob->jobid + 1; + + /* add thejob to the list of running jobs */ + if (!j_list->head) { + thejob = j_list->head = xmalloc(sizeof(*thejob)); + } else { + for (thejob = j_list->head; thejob->next; thejob = thejob->next) /* nothing */; + thejob->next = xmalloc(sizeof(*thejob)); + thejob = thejob->next; + } + + *thejob = *newjob; /* physically copy the struct job */ + thejob->next = NULL; + thejob->running_progs = thejob->num_progs; + thejob->stopped_progs = 0; + +#if ENABLE_LASH_JOB_CONTROL + if (inbg) { + /* we don't wait for background thejobs to return -- append it + to the list of backgrounded thejobs and leave it alone */ + printf("[%d] %d\n", thejob->jobid, + newjob->progs[newjob->num_progs - 1].pid); + last_jobid = newjob->jobid; + last_bg_pid = newjob->progs[newjob->num_progs - 1].pid; + } else { + newjob->job_list->fg = thejob; + + /* move the new process group into the foreground */ + /* Ignore errors since child could have already exited */ + tcsetpgrp(shell_terminal, newjob->pgrp); + } +#endif +} + +static int run_command(struct job *newjob, int inbg, int outpipe[2]) +{ + /* struct job *thejob; */ + int i; + int nextin, nextout; + int pipefds[2]; /* pipefd[0] is for reading */ + const struct built_in_command *x; + struct child_prog *child; + + nextin = 0; + for (i = 0; i < newjob->num_progs; i++) { + child = &(newjob->progs[i]); + + nextout = 1; + if ((i + 1) < newjob->num_progs) { + xpipe(pipefds); + nextout = pipefds[1]; + } else if (outpipe[1] != -1) { + nextout = outpipe[1]; + } + + /* Check if the command matches any non-forking builtins, + * but only if this is a simple command. + * Non-forking builtins within pipes have to fork anyway, + * and are handled in pseudo_exec. "echo foo | read bar" + * is doomed to failure, and doesn't work on bash, either. + */ + if (newjob->num_progs == 1) { + int rcode; + int squirrel[] = {-1, -1, -1}; + + /* Check if the command sets an environment variable. */ + if (strchr(child->argv[0], '=') != NULL) { + child->argv[1] = child->argv[0]; + return builtin_export(child); + } + + for (x = bltins; x <= &VEC_LAST(bltins); x++) { + if (strcmp(child->argv[0], x->cmd) == 0) { + setup_redirects(child, squirrel); + rcode = x->function(child); + restore_redirects(squirrel); + return rcode; + } + } +#if ENABLE_FEATURE_SH_STANDALONE + { + const struct bb_applet *a = find_applet_by_name(child->argv[i]); + if (a && a->nofork) { + setup_redirects(child, squirrel); + rcode = run_nofork_applet(a, child->argv + i); + restore_redirects(squirrel); + return rcode; + } + } +#endif + } + +#if BB_MMU + child->pid = fork(); +#else + child->pid = vfork(); +#endif + if (!child->pid) { + /* Set the handling for job control signals back to the default. */ + signal(SIGINT, SIG_DFL); + signal(SIGQUIT, SIG_DFL); + signal(SIGTSTP, SIG_DFL); + signal(SIGTTIN, SIG_DFL); + signal(SIGTTOU, SIG_DFL); + signal(SIGCHLD, SIG_DFL); + + /* Close all open filehandles. */ + while (close_me_list) + close((long)llist_pop(&close_me_list)); + + if (outpipe[1] != -1) { + close(outpipe[0]); + } + if (nextin != 0) { + dup2(nextin, 0); + close(nextin); + } + + if (nextout != 1) { + dup2(nextout, 1); + dup2(nextout, 2); /* Really? */ + close(nextout); + close(pipefds[0]); + } + + /* explicit redirects override pipes */ + setup_redirects(child,NULL); + + pseudo_exec(child); + } + if (outpipe[1] != -1) { + close(outpipe[1]); + } + + /* put our child in the process group whose leader is the + first process in this pipe */ + setpgid(child->pid, newjob->progs[0].pid); + if (nextin != 0) + close(nextin); + if (nextout != 1) + close(nextout); + + /* If there isn't another process, nextin is garbage + but it doesn't matter */ + nextin = pipefds[0]; + } + + newjob->pgrp = newjob->progs[0].pid; + + insert_job(newjob, inbg); + + return 0; +} + +static int busy_loop(FILE * input) +{ + char *command; + char *next_command = NULL; + struct job newjob; + int i; + int inbg = 0; + int status; +#if ENABLE_LASH_JOB_CONTROL + pid_t parent_pgrp; + /* save current owner of TTY so we can restore it on exit */ + parent_pgrp = tcgetpgrp(shell_terminal); +#endif + newjob.job_list = &job_list; + newjob.job_context = DEFAULT_CONTEXT; + + command = xzalloc(BUFSIZ); + + while (1) { + if (!job_list.fg) { + /* no job is in the foreground */ + + /* see if any background processes have exited */ + checkjobs(&job_list); + + if (!next_command) { + if (get_command_bufsiz(input, command)) + break; + next_command = command; + } + + if (!expand_arguments(next_command)) { + free(command); + command = xzalloc(BUFSIZ); + next_command = NULL; + continue; + } + + if (!parse_command(&next_command, &newjob, &inbg) && + newjob.num_progs) { + int pipefds[2] = { -1, -1 }; + debug_printf("job=%p fed to run_command by busy_loop()'\n", + &newjob); + run_command(&newjob, inbg, pipefds); + } + else { + free(command); + command = xzalloc(BUFSIZ); + next_command = NULL; + } + } else { + /* a job is running in the foreground; wait for it */ + i = 0; + while (!job_list.fg->progs[i].pid || + job_list.fg->progs[i].is_stopped == 1) i++; + + if (waitpid(job_list.fg->progs[i].pid, &status, WUNTRACED) < 0) { + if (errno != ECHILD) { + bb_perror_msg_and_die("waitpid(%d)", job_list.fg->progs[i].pid); + } + } + + if (WIFEXITED(status) || WIFSIGNALED(status)) { + /* the child exited */ + job_list.fg->running_progs--; + job_list.fg->progs[i].pid = 0; + + last_return_code = WEXITSTATUS(status); + + if (!job_list.fg->running_progs) { + /* child exited */ + remove_job(&job_list, job_list.fg); + job_list.fg = NULL; + } + } +#if ENABLE_LASH_JOB_CONTROL + else { + /* the child was stopped */ + job_list.fg->stopped_progs++; + job_list.fg->progs[i].is_stopped = 1; + + if (job_list.fg->stopped_progs == job_list.fg->running_progs) { + printf("\n" JOB_STATUS_FORMAT, job_list.fg->jobid, + "Stopped", job_list.fg->text); + job_list.fg = NULL; + } + } + + if (!job_list.fg) { + /* move the shell to the foreground */ + /* suppress messages when run from /linuxrc mag@sysgo.de */ + if (tcsetpgrp(shell_terminal, getpgrp()) && errno != ENOTTY) + bb_perror_msg("tcsetpgrp"); + } +#endif + } + } + free(command); + +#if ENABLE_LASH_JOB_CONTROL + /* return controlling TTY back to parent process group before exiting */ + if (tcsetpgrp(shell_terminal, parent_pgrp) && errno != ENOTTY) + bb_perror_msg("tcsetpgrp"); +#endif + + /* return exit status if called with "-c" */ + if (input == NULL && WIFEXITED(status)) + return WEXITSTATUS(status); + + return 0; +} + +#if ENABLE_FEATURE_CLEAN_UP +static void free_memory(void) +{ + free(cwd); + + if (job_list.fg && !job_list.fg->running_progs) { + remove_job(&job_list, job_list.fg); + } +} +#else +void free_memory(void); +#endif + +#if ENABLE_LASH_JOB_CONTROL +/* Make sure we have a controlling tty. If we get started under a job + * aware app (like bash for example), make sure we are now in charge so + * we don't fight over who gets the foreground */ +static void setup_job_control(void) +{ + int status; + pid_t shell_pgrp; + + /* Loop until we are in the foreground. */ + while ((status = tcgetpgrp(shell_terminal)) >= 0) { + shell_pgrp = getpgrp(); + if (status == shell_pgrp) { + break; + } + kill(- shell_pgrp, SIGTTIN); + } + + /* Ignore interactive and job-control signals. */ + signal(SIGINT, SIG_IGN); + signal(SIGQUIT, SIG_IGN); + signal(SIGTSTP, SIG_IGN); + signal(SIGTTIN, SIG_IGN); + signal(SIGTTOU, SIG_IGN); + signal(SIGCHLD, SIG_IGN); + + /* Put ourselves in our own process group. */ + setsid(); + shell_pgrp = getpid(); + setpgid(shell_pgrp, shell_pgrp); + + /* Grab control of the terminal. */ + tcsetpgrp(shell_terminal, shell_pgrp); +} +#else +static inline void setup_job_control(void) +{ +} +#endif + +int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int lash_main(int argc, char **argv) +{ + unsigned opt; + FILE *input = stdin; + + global_argc = argc; + global_argv = argv; + +#if ENABLE_FEATURE_EDITING + line_input_state = new_line_input_t(FOR_SHELL); +#endif + + /* These variables need re-initializing when recursing */ + last_jobid = 0; + close_me_list = NULL; + job_list.head = NULL; + job_list.fg = NULL; + last_return_code = 1; + + if (global_argv[0] && global_argv[0][0] == '-') { + FILE *prof_input; + prof_input = fopen("/etc/profile", "r"); + if (prof_input) { + llist_add_to(&close_me_list, (void *)(long)fileno(prof_input)); + /* Now run the file */ + busy_loop(prof_input); + fclose_if_not_stdin(prof_input); + llist_pop(&close_me_list); + } + } + + opt = getopt32(argv, "+ic:", &local_pending_command); +#define LASH_OPT_i (1<<0) +#define LASH_OPT_c (1<<1) + if (opt & LASH_OPT_c) { + input = NULL; + optind++; + global_argv += optind; + } + /* A shell is interactive if the `-i' flag was given, or if all of + * the following conditions are met: + * no -c command + * no arguments remaining or the -s flag given + * standard input is a terminal + * standard output is a terminal + * Refer to Posix.2, the description of the `sh' utility. */ + if (global_argv[optind] == NULL && input == stdin + && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO) + ) { + opt |= LASH_OPT_i; + } + setup_job_control(); + if (opt & LASH_OPT_i) { + /* Looks like they want an interactive shell */ + if (!ENABLE_FEATURE_SH_EXTRA_QUIET) { + printf("\n\n%s built-in shell (lash)\n" + "Enter 'help' for a list of built-in commands.\n\n", + bb_banner); + } + } else if (!local_pending_command && global_argv[optind]) { + //printf( "optind=%d argv[optind]='%s'\n", optind, argv[optind]); + input = xfopen(global_argv[optind], "r"); + /* be lazy, never mark this closed */ + llist_add_to(&close_me_list, (void *)(long)fileno(input)); + } + + /* initialize the cwd -- this is never freed...*/ + update_cwd(); + + if (ENABLE_FEATURE_CLEAN_UP) atexit(free_memory); + + if (ENABLE_FEATURE_EDITING) cmdedit_set_initial_prompt(); + else PS1 = NULL; + + return busy_loop(input); +}