/*
* lash -- the BusyBox Lame-Ass SHell
*
- * Copyright (C) 2000 by Lineo, inc.
+ * Copyright (C) 1999,2000,2001 by Lineo, inc.
* Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
*
* Based in part on ladsh.c by Michael K. Johnson and Erik W. Troan, which is
*
*/
+/* The parsing engine of this program is officially at a dead-end.
+ * Future work in that direction should move to the work posted
+ * at http://doolittle.faludi.com/~larry/parser.html .
+ * A start on the integration of that work with the rest of sh.c
+ * is at http://codepoet.org/sh.c .
+ */
//
-//This works pretty well now, and is not on by default.
+//This works pretty well now, and is now on by default.
#define BB_FEATURE_SH_ENVIRONMENT
//
//Backtick support has some problems, use at your own risk!
//
//If, then, else, etc. support.. This should now behave basically
//like any other Bourne shell...
-//#define BB_FEATURE_SH_IF_EXPRESSIONS
+#define BB_FEATURE_SH_IF_EXPRESSIONS
//
/* This is currently a little broken... */
//#define HANDLE_CONTINUATION_CHARS
#include <getopt.h>
#include "cmdedit.h"
-#define MAX_LINE 256 /* size of input buffer for cwd data */
-#define MAX_READ 128 /* size of input buffer for `read' builtin */
+static const int MAX_LINE = 256; /* size of input buffer for cwd data */
+static const int MAX_READ = 128; /* size of input buffer for `read' builtin */
#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
extern size_t NUM_APPLETS;
static const unsigned int IF_FALSE_CONTEXT=0x4;
static const unsigned int THEN_EXP_CONTEXT=0x8;
static const unsigned int ELSE_EXP_CONTEXT=0x10;
-unsigned int shell_context = 0;
-
struct jobset {
int (*function) (struct child_prog *); /* function ptr */
};
+struct close_me {
+ int fd;
+ struct close_me *next;
+};
+
/* function prototypes for builtins */
static int builtin_cd(struct child_prog *cmd);
static int builtin_env(struct child_prog *dummy);
static int builtin_then(struct child_prog *cmd);
static int builtin_else(struct child_prog *cmd);
static int builtin_fi(struct child_prog *cmd);
+/* function prototypes for shell stuff */
+static int run_command_predicate(char *cmd);
#endif
/* function prototypes for shell stuff */
+static void mark_open(int fd);
+static void mark_closed(int fd);
static void checkjobs(struct jobset *job_list);
static int get_command(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 run_command_predicate(char *cmd);
static int busy_loop(FILE * input);
{NULL, NULL, NULL}
};
-static char prompt[3];
+
+/* Variables we export */
+unsigned int shell_context; /* Used in cmdedit.c to reset the
+ context when someone hits ^C */
+
+
+/* Globals that are static to this file */
static char *cwd;
static char *local_pending_command = NULL;
-static char *prompt_str = NULL;
static struct jobset job_list = { NULL, NULL };
static int argc;
static char **argv;
+static struct close_me *close_me_head = NULL;
#ifdef BB_FEATURE_SH_ENVIRONMENT
static int last_bg_pid=-1;
static int last_return_code=-1;
static inline void debug_printf(const char *format, ...) { }
#endif
-#ifdef BB_FEATURE_SH_COMMAND_EDITING
-static inline void win_changed(int junk)
-{
- struct winsize win = { 0, 0, 0, 0 };
- ioctl(0, TIOCGWINSZ, &win);
- if (win.ws_col > 0) {
- cmdedit_setwidth( win.ws_col - 1);
- }
-}
-#else
-static inline void win_changed(int junk) {}
-#endif
-
/*
Most builtins need access to the struct child_prog that has
their arguments, previously coded as cmd->progs[0]. That coding
char **e;
for (e = environ; *e; e++) {
- fprintf(stdout, "%s\n", *e);
+ printf( "%s\n", *e);
}
return (0);
}
int i, jobNum;
struct job *job=NULL;
+ if (!child->argv[1] || child->argv[2]) {
+ error_msg("%s: exactly one argument is expected\n",
+ child->argv[0]);
+ return EXIT_FAILURE;
+ }
- if (!child->argv[1] || child->argv[2]) {
- error_msg("%s: exactly one argument is expected\n",
- child->argv[0]);
- return EXIT_FAILURE;
- }
- if (sscanf(child->argv[1], "%%%d", &jobNum) != 1) {
- error_msg("%s: bad argument '%s'\n",
- child->argv[0], child->argv[1]);
- return EXIT_FAILURE;
- }
- for (job = child->family->job_list->head; job; job = job->next) {
- if (job->jobid == jobNum) {
- break;
- }
+ if (sscanf(child->argv[1], "%%%d", &jobNum) != 1) {
+ error_msg("%s: bad argument '%s'\n",
+ child->argv[0], child->argv[1]);
+ return EXIT_FAILURE;
+ }
+
+ for (job = child->family->job_list->head; job; job = job->next) {
+ if (job->jobid == jobNum) {
+ break;
}
+ }
if (!job) {
error_msg("%s: unknown job %d\n",
/* Make this job the foreground job */
/* suppress messages when run from /linuxrc mag@sysgo.de */
if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
- perror("tcsetpgrp");
+ perror_msg("tcsetpgrp");
child->family->job_list->fg = job;
}
static int builtin_pwd(struct child_prog *dummy)
{
getcwd(cwd, MAX_LINE);
- fprintf(stdout, "%s\n", cwd);
+ printf( "%s\n", cwd);
return EXIT_SUCCESS;
}
}
cmd->job_context |= ELSE_EXP_CONTEXT;
- debug_printf("job=%p builtin_else set job context to %x\n", child->family, cmd->job_context);
+ debug_printf("job=%p builtin_else set job context to %x\n", cmd, cmd->job_context);
/* Now run the 'else' command */
debug_printf( "'else' now running '%s'\n", charptr1);
{
FILE *input;
int status;
+ int fd;
if (child->argv[1] == NULL)
return EXIT_FAILURE;
input = fopen(child->argv[1], "r");
if (!input) {
- fprintf(stdout, "Couldn't open file '%s'\n", child->argv[1]);
+ printf( "Couldn't open file '%s'\n", child->argv[1]);
return EXIT_FAILURE;
}
+ fd=fileno(input);
+ mark_open(fd);
/* Now run the file */
status = busy_loop(input);
fclose(input);
+ mark_closed(fd);
return (status);
}
static int builtin_unset(struct child_prog *child)
{
if (child->argv[1] == NULL) {
- fprintf(stdout, "unset: parameter required.\n");
+ printf( "unset: parameter required.\n");
return EXIT_FAILURE;
}
unsetenv(child->argv[1]);
return EXIT_SUCCESS;
}
+#ifdef BB_FEATURE_SH_IF_EXPRESSIONS
/* currently used by if/then/else.
- * Needlessly (?) forks and reparses the command line.
- * But pseudo_exec on the pre-parsed args doesn't have the
- * "fork, stick around until the child exits, and find it's return code"
- * functionality. The fork is not needed if the predicate is
- * non-forking builtin, and maybe not even if it's a forking builtin.
- * applets pretty clearly need the fork.
+ *
+ * Reparsing the command line for this purpose is gross,
+ * incorrect, and fundamentally unfixable; in particular,
+ * think about what happens with command substitution.
+ * We really need to pull out the run, wait, return status
+ * functionality out of busy_loop so we can child->argv++
+ * and use that, without going back through parse_command.
*/
static int run_command_predicate(char *cmd)
{
local_pending_command[n]='\0';
return( busy_loop(NULL));
}
+#endif
+
+static void mark_open(int fd)
+{
+ struct close_me *new = xmalloc(sizeof(struct close_me));
+ new->fd = fd;
+ new->next = close_me_head;
+ close_me_head = new;
+}
+
+static void mark_closed(int fd)
+{
+ struct close_me *tmp;
+ if (close_me_head == NULL || close_me_head->fd != fd)
+ error_msg_and_die("corrupt close_me");
+ tmp = close_me_head;
+ close_me_head = close_me_head->next;
+ free(tmp);
+}
+
+static void close_all()
+{
+ struct close_me *c;
+ for (c=close_me_head; c; c=c->next) {
+ close(c->fd);
+ }
+ close_me_head = NULL;
+}
+
/* free up all memory from a job */
static void free_job(struct job *cmd)
}
if (childpid == -1 && errno != ECHILD)
- perror("waitpid");
+ perror_msg("waitpid");
}
-static int setup_redirects(struct child_prog *prog)
+/* 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;
}
if (openfd != redir->fd) {
+ if (squirrel && redir->fd < 3) {
+ squirrel[redir->fd] = dup(redir->fd);
+ }
dup2(openfd, redir->fd);
close(openfd);
}
return 0;
}
-
-static int get_command(FILE * source, char *command)
+static void restore_redirects(int squirrel[])
{
- char user[9],buf[255],*s;
-
- if (source == NULL) {
- if (local_pending_command) {
- /* a command specified (-c option): return it & mark it done */
- strcpy(command, local_pending_command);
- free(local_pending_command);
- local_pending_command = NULL;
- return 0;
+ 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);
}
- return 1;
}
+}
- if (shell_context == 0) {
+static char* setup_prompt_string(int state)
+{
+ char user[9],buf[255],*s;
+ char prompt[3];
+ char prompt_str[BUFSIZ];
+
+ /* Set up the prompt */
+ if (state == 0) {
/* get User Name and setup prompt */
strcpy(prompt,( geteuid() != 0 ) ? "$ ":"# ");
my_getpwuid(user, geteuid());
-
+
/* get HostName */
gethostname(buf, 255);
s = strchr(buf, '.');
} else {
strcpy(prompt,"> ");
}
-
+
+ if (state == 0) {
+ snprintf(prompt_str, BUFSIZ-1, "[%s@%s %s]%s", user, buf,
+ get_last_path_component(cwd), prompt);
+ } else {
+ sprintf(prompt_str, "%s", prompt);
+ }
+ return(strdup(prompt_str)); /* Must free this memory */
+}
+
+static int get_command(FILE * source, char *command)
+{
+ char *prompt_str;
+
+ if (source == NULL) {
+ if (local_pending_command) {
+ /* a command specified (-c option): return it & mark it done */
+ strcpy(command, local_pending_command);
+ free(local_pending_command);
+ local_pending_command = NULL;
+ return 0;
+ }
+ return 1;
+ }
+
if (source == stdin) {
-#ifdef BB_FEATURE_SH_COMMAND_EDITING
- int len;
+ prompt_str = setup_prompt_string(shell_context);
+#ifdef BB_FEATURE_SH_COMMAND_EDITING
/*
** enable command line editing only while a command line
** is actually being read; otherwise, we'll end up bequeathing
** child processes (rob@sysgo.de)
*/
cmdedit_init();
- signal(SIGWINCH, win_changed);
- debug_printf( "in get_command() -- job_context=%d\n", shell_context);
- fflush(stdout);
- if (shell_context == 0) {
- len=fprintf(stdout, "[%s@%s %s]%s", user, buf,
- get_last_path_component(cwd), prompt);
- } else {
- len=fprintf(stdout, "%s", prompt);
- }
- fflush(stdout);
- prompt_str=(char*)xmalloc(sizeof(char)*(len+1));
- if (shell_context == 0) {
- sprintf(prompt_str, "[%s@%s %s]%s", user, buf,
- get_last_path_component(cwd), prompt);
- } else {
- sprintf(prompt_str, "%s", prompt);
- }
cmdedit_read_input(prompt_str, command);
- free( prompt_str);
+ free(prompt_str);
cmdedit_terminate();
- signal(SIGWINCH, SIG_DFL);
return 0;
#else
- i=strlen(cwd);
- i--;
- if (i>1){
- while ((i>0) && (*(cwd+i)!='/') ) i--;
- if (*(cwd+i)=='/') i++;
- }
-
- fprintf(stdout, "[%s@%s %s]%s",user, buf, (cwd+i), prompt);
- fflush(stdout);
+ fputs(prompt_str, stdout);
+ free(prompt_str);
#endif
}
#ifdef BB_FEATURE_SH_BACKTICKS
case '`':
/* Exec a backtick-ed command */
+ /* Besides any previous brokenness, I have not
+ * updated backtick handling for close_me support.
+ * I don't know if it needs it or not. -- LRD */
{
char* charptr1=NULL, *charptr2;
char* ptr=NULL;
struct BB_applet search_applet, *applet;
#endif
- /* Check if the command matches any of the forking builtins.
- * XXX It would probably be wise to check for non-forking builtins
- * here as well, since in some context the non-forking path
- * is disabled or bypassed. See comment in run_command.
+ /* 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.
*/
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ exit(x->function(child));
+ }
+ }
+
+ /* Check if the command matches any of the forking builtins. */
for (x = bltins_forking; x->cmd; x++) {
if (strcmp(child->argv[0], x->cmd) == 0) {
applet_name=x->cmd;
#endif
execvp(child->argv[0], child->argv);
- error_msg_and_die("%s: %s\n", child->argv[0],
- strerror(errno));
+ perror_msg_and_die("%s", child->argv[0]);
}
static void insert_job(struct job *newjob, int inbg)
/* move the new process group into the foreground */
/* suppress messages when run from /linuxrc mag@sysgo.de */
if (tcsetpgrp(0, newjob->pgrp) && errno != ENOTTY)
- perror("tcsetpgrp");
+ perror_msg("tcsetpgrp");
}
}
}
#endif
- /* Check if the command matches any non-forking builtins.
- * XXX should probably skip this test, and fork anyway, if
- * there redirects of some kind demand forking to work right.
- * pseudo_exec would then need to handle the non-forking command
- * in a forked context.
+ /* 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.
*/
- for (x = bltins; x->cmd; x++) {
- if (strcmp(child->argv[0], x->cmd) == 0 ) {
- return(x->function(child));
+ if (newjob->num_progs == 1) {
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ int squirrel[] = {-1, -1, -1};
+ int rcode;
+ setup_redirects(child, squirrel);
+ rcode = x->function(child);
+ restore_redirects(squirrel);
+ return rcode;
+ }
}
}
if (!(child->pid = fork())) {
signal(SIGTTOU, SIG_DFL);
+ close_all();
+
if (outpipe[1]!=-1) {
close(outpipe[0]);
}
}
/* explicit redirects override pipes */
- setup_redirects(child);
+ setup_redirects(child,NULL);
pseudo_exec(child);
}
while (!job_list.fg->progs[i].pid ||
job_list.fg->progs[i].is_stopped == 1) i++;
- waitpid(job_list.fg->progs[i].pid, &status, WUNTRACED);
+ if (waitpid(job_list.fg->progs[i].pid, &status, WUNTRACED)<0)
+ perror_msg_and_die("waitpid(%d)",job_list.fg->progs[i].pid);
if (WIFEXITED(status) || WIFSIGNALED(status)) {
/* the child exited */
/* move the shell to the foreground */
/* suppress messages when run from /linuxrc mag@sysgo.de */
if (tcsetpgrp(0, getpid()) && errno != ENOTTY)
- perror("tcsetpgrp");
+ perror_msg("tcsetpgrp");
}
}
}
/* return controlling TTY back to parent process group before exiting */
if (tcsetpgrp(0, parent_pgrp))
- perror("tcsetpgrp");
+ perror_msg("tcsetpgrp");
/* return exit status if called with "-c" */
if (input == NULL && WIFEXITED(status))
#ifdef BB_FEATURE_CLEAN_UP
void free_memory(void)
{
- if (prompt_str)
- free(prompt_str);
if (cwd)
free(cwd);
if (local_pending_command)
argc = argc_l;
argv = argv_l;
+ shell_context = 0;
+ cwd=NULL;
+#ifdef BB_FEATURE_SH_STANDALONE_SHELL
+ /* These variables need re-initializing when recursing */
+ local_pending_command = NULL;
+ job_list.head = NULL;
+ job_list.fg = NULL;
+#ifdef BB_FEATURE_SH_ENVIRONMENT
+ last_bg_pid=-1;
+ last_return_code=-1;
+ show_x_trace=FALSE;
+#endif
+#endif
if (argv[0] && argv[0][0] == '-') {
- FILE *input;
- input = fopen("/etc/profile", "r");
- if (!input) {
- fprintf(stdout, "Couldn't open file '/etc/profile'\n");
- } else {
- /* Now run the file */
- busy_loop(input);
- fclose(input);
- }
+ FILE *prof_input;
+ prof_input = fopen("/etc/profile", "r");
+ if (!prof_input) {
+ printf( "Couldn't open file '/etc/profile'\n");
+ } else {
+ int tmp_fd = fileno(prof_input);
+ mark_open(tmp_fd);
+ /* Now run the file */
+ busy_loop(prof_input);
+ fclose(prof_input);
+ mark_closed(tmp_fd);
+ }
}
while ((opt = getopt(argc_l, argv_l, "cxi")) > 0) {
interactive=TRUE;
}
if (interactive==TRUE) {
- //fprintf(stdout, "optind=%d argv[optind]='%s'\n", optind, argv[optind]);
+ //printf( "optind=%d argv[optind]='%s'\n", optind, argv[optind]);
/* Looks like they want an interactive shell */
- fprintf(stdout, "\n\nBusyBox v%s (%s) Built-in shell (lash)\n", BB_VER, BB_BT);
- fprintf(stdout, "Enter 'help' for a list of built-in commands.\n\n");
+ printf( "\n\nBusyBox v%s (%s) Built-in shell (lash)\n", BB_VER, BB_BT);
+ printf( "Enter 'help' for a list of built-in commands.\n\n");
} else if (local_pending_command==NULL) {
- //fprintf(stdout, "optind=%d argv[optind]='%s'\n", optind, argv[optind]);
+ //printf( "optind=%d argv[optind]='%s'\n", optind, argv[optind]);
input = xfopen(argv[optind], "r");
+ mark_open(fileno(input)); /* be lazy, never mark this closed */
}
/* initialize the cwd -- this is never freed...*/
atexit(free_memory);
#endif
- win_changed(0);
return (busy_loop(input));
}