Extract usage information into a separate file.
[oweals/busybox.git] / shell / lash.c
index 56d94258cdf6331ed3312958488b1473f7ec497f..9b3435304926289db4301c2ccd7c781a7e63361c 100644 (file)
@@ -41,7 +41,7 @@
 #include "cmdedit.h"
 #endif
 
-
+#define MAX_READ       128     /* size of input buffer for `read' builtin */
 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
 
 
@@ -89,62 +89,62 @@ struct builtInCommand {
        int (*function) (struct job *, struct jobSet * jobList);        /* function ptr */
 };
 
-/* Some function prototypes */
-static int shell_cd(struct job *cmd, struct jobSet *junk);
-static int shell_env(struct job *dummy, struct jobSet *junk);
-static int shell_exit(struct job *cmd, struct jobSet *junk);
-static int shell_fg_bg(struct job *cmd, struct jobSet *jobList);
-static int shell_help(struct job *cmd, struct jobSet *junk);
-static int shell_jobs(struct job *dummy, struct jobSet *jobList);
-static int shell_pwd(struct job *dummy, struct jobSet *junk);
-static int shell_export(struct job *cmd, struct jobSet *junk);
-static int shell_source(struct job *cmd, struct jobSet *jobList);
-static int shell_unset(struct job *cmd, struct jobSet *junk);
-
+/* function prototypes for builtins */
+static int builtin_cd(struct job *cmd, struct jobSet *junk);
+static int builtin_env(struct job *dummy, struct jobSet *junk);
+static int builtin_exit(struct job *cmd, struct jobSet *junk);
+static int builtin_fg_bg(struct job *cmd, struct jobSet *jobList);
+static int builtin_help(struct job *cmd, struct jobSet *junk);
+static int builtin_jobs(struct job *dummy, struct jobSet *jobList);
+static int builtin_pwd(struct job *dummy, struct jobSet *junk);
+static int builtin_export(struct job *cmd, struct jobSet *junk);
+static int builtin_source(struct job *cmd, struct jobSet *jobList);
+static int builtin_unset(struct job *cmd, struct jobSet *junk);
+static int builtin_read(struct job *cmd, struct jobSet *junk);
+
+
+/* function prototypes for shell stuff */
 static void checkJobs(struct jobSet *jobList);
 static int getCommand(FILE * source, char *command);
-static int parseCommand(char **commandPtr, struct job *job, int *isBg);
+static int parseCommand(char **commandPtr, struct job *job, struct jobSet *jobList, int *isBg);
 static int setupRedirections(struct childProgram *prog);
-static int runCommand(struct job newJob, struct jobSet *jobList, int inBg);
+static int runCommand(struct job *newJob, struct jobSet *jobList, int inBg);
 static int busy_loop(FILE * input);
 
 
-/* Table of built-in functions */
+/* 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 struct builtInCommand bltins[] = {
-       {"bg", "Resume a job in the background", "bg [%%job]", shell_fg_bg},
-       {"cd", "Change working directory", "cd [dir]", shell_cd},
-       {"exit", "Exit from shell()", "exit", shell_exit},
-       {"fg", "Bring job into the foreground", "fg [%%job]", shell_fg_bg},
-       {"jobs", "Lists the active jobs", "jobs", shell_jobs},
-       {"export", "Set environment variable", "export [VAR=value]", shell_export},
-       {"unset", "Unset environment variable", "unset VAR", shell_unset},
+       {"bg", "Resume a job in the background", "bg [%%job]", builtin_fg_bg},
+       {"cd", "Change working directory", "cd [dir]", builtin_cd},
+       {"exit", "Exit from shell()", "exit", builtin_exit},
+       {"fg", "Bring job into the foreground", "fg [%%job]", builtin_fg_bg},
+       {"jobs", "Lists the active jobs", "jobs", builtin_jobs},
+       {"export", "Set environment variable", "export [VAR=value]", builtin_export},
+       {"unset", "Unset environment variable", "unset VAR", builtin_unset},
+       {"read", "Input environment variable", "read [VAR]", builtin_read},
        {NULL, NULL, NULL, NULL}
 };
 
-/* Table of built-in functions */
+/* Table of forking built-in functions (things that fork cannot change global
+ * variables in the parent process, such as the current working directory) */
 static struct builtInCommand bltins_forking[] = {
-       {"env", "Print all environment variables", "env", shell_env},
-       {"pwd", "Print current directory", "pwd", shell_pwd},
-       {".", "Source-in and run commands in a file", ". filename", shell_source},
-       {"help", "List shell built-in commands", "help", shell_help},
+       {"env", "Print all environment variables", "env", builtin_env},
+       {"pwd", "Print current directory", "pwd", builtin_pwd},
+       {".", "Source-in and run commands in a file", ". filename", builtin_source},
+       {"help", "List shell built-in commands", "help", builtin_help},
        {NULL, NULL, NULL, NULL}
 };
 
-static const char shell_usage[] =
-
-       "sh [FILE]...\n" 
-#ifndef BB_FEATURE_TRIVIAL_HELP
-       "\nlash: The BusyBox command interpreter (shell).\n\n"
-#endif
-       ;
-
-static char cwd[1024];
 static char *prompt = "# ";
+static char *cwd = NULL;
+static char *local_pending_command = NULL;
 
 #ifdef BB_FEATURE_SH_COMMAND_EDITING
-void win_changed(int sig)
+void win_changed(int junk)
 {
-       struct winsize win = { 0, 0 };
+       struct winsize win = { 0, 0, 0, 0 };
        ioctl(0, TIOCGWINSZ, &win);
        if (win.ws_col > 0) {
                cmdedit_setwidth( win.ws_col - 1);
@@ -154,7 +154,7 @@ void win_changed(int sig)
 
 
 /* built-in 'cd <path>' handler */
-static int shell_cd(struct job *cmd, struct jobSet *junk)
+static int builtin_cd(struct job *cmd, struct jobSet *junk)
 {
        char *newdir;
 
@@ -172,7 +172,7 @@ static int shell_cd(struct job *cmd, struct jobSet *junk)
 }
 
 /* built-in 'env' handler */
-static int shell_env(struct job *dummy, struct jobSet *junk)
+static int builtin_env(struct job *dummy, struct jobSet *junk)
 {
        char **e;
 
@@ -183,7 +183,7 @@ static int shell_env(struct job *dummy, struct jobSet *junk)
 }
 
 /* built-in 'exit' handler */
-static int shell_exit(struct job *cmd, struct jobSet *junk)
+static int builtin_exit(struct job *cmd, struct jobSet *junk)
 {
        if (!cmd->progs[0].argv[1] == 1)
                exit TRUE;
@@ -192,19 +192,19 @@ static int shell_exit(struct job *cmd, struct jobSet *junk)
 }
 
 /* built-in 'fg' and 'bg' handler */
-static int shell_fg_bg(struct job *cmd, struct jobSet *jobList)
+static int builtin_fg_bg(struct job *cmd, struct jobSet *jobList)
 {
        int i, jobNum;
        struct job *job=NULL;
 
        if (!jobList->head) {
                if (!cmd->progs[0].argv[1] || cmd->progs[0].argv[2]) {
-                       fprintf(stderr, "%s: exactly one argument is expected\n",
+                       errorMsg("%s: exactly one argument is expected\n",
                                        cmd->progs[0].argv[0]);
                        return FALSE;
                }
                if (sscanf(cmd->progs[0].argv[1], "%%%d", &jobNum) != 1) {
-                       fprintf(stderr, "%s: bad argument '%s'\n",
+                       errorMsg("%s: bad argument '%s'\n",
                                        cmd->progs[0].argv[0], cmd->progs[0].argv[1]);
                        return FALSE;
                        for (job = jobList->head; job; job = job->next) {
@@ -218,15 +218,16 @@ static int shell_fg_bg(struct job *cmd, struct jobSet *jobList)
        }
 
        if (!job) {
-               fprintf(stderr, "%s: unknown job %d\n",
+               errorMsg("%s: unknown job %d\n",
                                cmd->progs[0].argv[0], jobNum);
                return FALSE;
        }
 
        if (*cmd->progs[0].argv[0] == 'f') {
                /* Make this job the foreground job */
-               if (tcsetpgrp(0, job->pgrp))
-                       perror("tcsetpgrp");
+               /* suppress messages when run from /linuxrc mag@sysgo.de */
+               if (tcsetpgrp(0, job->pgrp) && errno != ENOTTY)
+                       perror("tcsetpgrp"); 
                jobList->fg = job;
        }
 
@@ -242,7 +243,7 @@ static int shell_fg_bg(struct job *cmd, struct jobSet *jobList)
 }
 
 /* built-in 'help' handler */
-static int shell_help(struct job *cmd, struct jobSet *junk)
+static int builtin_help(struct job *dummy, struct jobSet *junk)
 {
        struct builtInCommand *x;
 
@@ -259,7 +260,7 @@ static int shell_help(struct job *cmd, struct jobSet *junk)
 }
 
 /* built-in 'jobs' handler */
-static int shell_jobs(struct job *dummy, struct jobSet *jobList)
+static int builtin_jobs(struct job *dummy, struct jobSet *jobList)
 {
        struct job *job;
        char *statusString;
@@ -277,7 +278,7 @@ static int shell_jobs(struct job *dummy, struct jobSet *jobList)
 
 
 /* built-in 'pwd' handler */
-static int shell_pwd(struct job *dummy, struct jobSet *junk)
+static int builtin_pwd(struct job *dummy, struct jobSet *junk)
 {
        getcwd(cwd, sizeof(cwd));
        fprintf(stdout, "%s\n", cwd);
@@ -285,12 +286,12 @@ static int shell_pwd(struct job *dummy, struct jobSet *junk)
 }
 
 /* built-in 'export VAR=value' handler */
-static int shell_export(struct job *cmd, struct jobSet *junk)
+static int builtin_export(struct job *cmd, struct jobSet *junk)
 {
        int res;
 
        if (!cmd->progs[0].argv[1] == 1) {
-               return (shell_env(cmd, junk));
+               return (builtin_env(cmd, junk));
        }
        res = putenv(cmd->progs[0].argv[1]);
        if (res)
@@ -298,8 +299,42 @@ static int shell_export(struct job *cmd, struct jobSet *junk)
        return (res);
 }
 
+/* built-in 'read VAR' handler */
+static int builtin_read(struct job *cmd, struct jobSet *junk)
+{
+       int res = 0, len, newlen;
+       char *s;
+       char string[MAX_READ];
+
+       if (cmd->progs[0].argv[1]) {
+               /* argument (VAR) given: put "VAR=" into buffer */
+               strcpy(string, cmd->progs[0].argv[1]);
+               len = strlen(string);
+               string[len++] = '=';
+               string[len]   = '\0';
+               fgets(&string[len], sizeof(string) - len, stdin);       /* read string */
+               newlen = strlen(string);
+               if(newlen > len)
+                       string[--newlen] = '\0';        /* chomp trailing newline */
+               /*
+               ** string should now contain "VAR=<value>"
+               ** copy it (putenv() won't do that, so we must make sure
+               ** the string resides in a static buffer!)
+               */
+               res = -1;
+               if((s = strdup(string)))
+                       res = putenv(s);
+               if (res)
+                       fprintf(stdout, "read: %s\n", strerror(errno));
+       }
+       else
+               fgets(string, sizeof(string), stdin);
+
+       return (res);
+}
+
 /* Built-in '.' handler (read-in and execute commands from file) */
-static int shell_source(struct job *cmd, struct jobSet *junk)
+static int builtin_source(struct job *cmd, struct jobSet *junk)
 {
        FILE *input;
        int status;
@@ -320,7 +355,7 @@ static int shell_source(struct job *cmd, struct jobSet *junk)
 }
 
 /* built-in 'unset VAR' handler */
-static int shell_unset(struct job *cmd, struct jobSet *junk)
+static int builtin_unset(struct job *cmd, struct jobSet *junk)
 {
        if (!cmd->progs[0].argv[1] == 1) {
                fprintf(stdout, "unset: parameter required.\n");
@@ -346,6 +381,7 @@ static void freeJob(struct job *cmd)
        if (cmd->text)
                free(cmd->text);
        free(cmd->cmdBuf);
+       memset(cmd, 0, sizeof(struct job));
 }
 
 /* remove a job from the jobList */
@@ -411,13 +447,24 @@ static void checkJobs(struct jobSet *jobList)
 
 static int getCommand(FILE * source, char *command)
 {
+       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;
                char *promptStr;
                len=fprintf(stdout, "%s %s", cwd, prompt);
                fflush(stdout);
-               promptStr=(char*)malloc(sizeof(char)*(len+1));
+               promptStr=(char*)xmalloc(sizeof(char)*(len+1));
                sprintf(promptStr, "%s %s", cwd, prompt);
                cmdedit_read_input(promptStr, command);
                free( promptStr);
@@ -448,7 +495,7 @@ static void globLastArgument(struct childProgram *prog, int *argcPtr,
        int rc;
        int flags;
        int i;
-       char *src, *dst;
+       char *src, *dst, *var;
 
        if (argc > 1) {                         /* cmd->globResult is already initialized */
                flags = GLOB_APPEND;
@@ -458,10 +505,13 @@ static void globLastArgument(struct childProgram *prog, int *argcPtr,
                flags = 0;
                i = 0;
        }
+       /* do shell variable substitution */
+       if(*prog->argv[argc - 1] == '$' && (var = getenv(prog->argv[argc - 1] + 1)))
+               prog->argv[argc - 1] = var;
 
        rc = glob(prog->argv[argc - 1], flags, NULL, &prog->globResult);
        if (rc == GLOB_NOSPACE) {
-               fprintf(stderr, "out of space during glob operation\n");
+               errorMsg("out of space during glob operation\n");
                return;
        } else if (rc == GLOB_NOMATCH ||
                           (!rc && (prog->globResult.gl_pathc - i) == 1 &&
@@ -493,7 +543,7 @@ static void globLastArgument(struct childProgram *prog, int *argcPtr,
    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 parseCommand(char **commandPtr, struct job *job, int *isBg)
+static int parseCommand(char **commandPtr, struct job *job, struct jobSet *jobList, int *isBg)
 {
        char *command;
        char *returnCommand = NULL;
@@ -512,22 +562,22 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
 
        /* this handles empty lines or leading '#' characters */
        if (!**commandPtr || (**commandPtr == '#')) {
-               job->numProgs = 0;
-               *commandPtr = NULL;
+               job->numProgs=0;
                return 0;
        }
 
        *isBg = 0;
        job->numProgs = 1;
-       job->progs = malloc(sizeof(*job->progs));
+       job->progs = xmalloc(sizeof(*job->progs));
 
        /* We set the argv elements to point inside of this string. The 
-          memory is freed by freeJob(). 
+          memory is freed by freeJob(). 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 = calloc(1, strlen(*commandPtr) + 1);
+       job->cmdBuf = command = calloc(1, 2*strlen(*commandPtr) + 1);
        job->text = NULL;
 
        prog = job->progs;
@@ -537,7 +587,7 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
        prog->isStopped = 0;
 
        argvAlloced = 5;
-       prog->argv = malloc(sizeof(*prog->argv) * argvAlloced);
+       prog->argv = xmalloc(sizeof(*prog->argv) * argvAlloced);
        prog->argv[0] = job->cmdBuf;
 
        buf = command;
@@ -549,7 +599,7 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                        if (*src == '\\') {
                                src++;
                                if (!*src) {
-                                       fprintf(stderr, "character expected after \\\n");
+                                       errorMsg("character expected after \\\n");
                                        freeJob(job);
                                        return 1;
                                }
@@ -570,9 +620,8 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                                                                                 sizeof(*prog->argv) *
                                                                                 argvAlloced);
                                }
-                               prog->argv[argc] = buf;
-
                                globLastArgument(prog, &argc, &argvAlloced);
+                               prog->argv[argc] = buf;
                        }
                } else
                        switch (*src) {
@@ -602,6 +651,7 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                                        if (*chptr && *prog->argv[argc]) {
                                                buf++, argc++;
                                                globLastArgument(prog, &argc, &argvAlloced);
+                                               prog->argv[argc] = buf;
                                        }
                                }
 
@@ -628,8 +678,9 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                                        chptr++;
 
                                if (!*chptr) {
-                                       fprintf(stderr, "file name expected after %c\n", *src);
+                                       errorMsg("file name expected after %c\n", *src);
                                        freeJob(job);
+                                       job->numProgs=0;
                                        return 1;
                                }
 
@@ -646,8 +697,9 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                                if (*prog->argv[argc])
                                        argc++;
                                if (!argc) {
-                                       fprintf(stderr, "empty command in pipe\n");
+                                       errorMsg("empty command in pipe1\n");
                                        freeJob(job);
+                                       job->numProgs=0;
                                        return 1;
                                }
                                prog->argv[argc] = NULL;
@@ -663,7 +715,7 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                                argc = 0;
 
                                argvAlloced = 5;
-                               prog->argv = malloc(sizeof(*prog->argv) * argvAlloced);
+                               prog->argv = xmalloc(sizeof(*prog->argv) * argvAlloced);
                                prog->argv[0] = ++buf;
 
                                src++;
@@ -671,7 +723,9 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                                        src++;
 
                                if (!*src) {
-                                       fprintf(stderr, "empty command in pipe\n");
+                                       errorMsg("empty command in pipe2\n");
+                                       freeJob(job);
+                                       job->numProgs=0;
                                        return 1;
                                }
                                src--;                  /* we'll ++ it at the end of the loop */
@@ -688,13 +742,40 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
                        case '\\':
                                src++;
                                if (!*src) {
+                                       errorMsg("character expected after \\\n");
                                        freeJob(job);
-                                       fprintf(stderr, "character expected after \\\n");
                                        return 1;
                                }
                                if (*src == '*' || *src == '[' || *src == ']'
                                        || *src == '?') *buf++ = '\\';
                                /* fallthrough */
+                       case '`':
+                               /* Exec a backtick-ed command */
+                               {
+                                       char* newcmd=NULL;
+                                       char* ptr=NULL;
+                                       struct job newJob;
+
+                                       ptr=strchr(++src, '`');
+                                       if (ptr==NULL) {
+                                               fprintf(stderr, "Unmatched '`' in command\n");
+                                               freeJob(job);
+                                               return 1;
+                                       }
+
+                                       newcmd = xmalloc(1+ptr-src);
+                                       snprintf(newcmd, 1+ptr-src, src);
+
+                                       if (!parseCommand(&newcmd, &newJob, jobList, isBg) &&
+                                                       newJob.numProgs) {
+                                               runCommand(&newJob, jobList, *isBg);
+                                       }
+
+                                       /* Clip out the the backticked command from the string */
+                                       memmove(--src, ptr, strlen(ptr)+1);
+                                       free(newcmd);
+                               }
+                               break;
                        default:
                                *buf++ = *src;
                        }
@@ -713,12 +794,12 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
        prog->argv[argc] = NULL;
 
        if (!returnCommand) {
-               job->text = malloc(strlen(*commandPtr) + 1);
+               job->text = xmalloc(strlen(*commandPtr) + 1);
                strcpy(job->text, *commandPtr);
        } else {
                /* This leaves any trailing spaces, which is a bit sloppy */
                count = returnCommand - *commandPtr;
-               job->text = malloc(count + 1);
+               job->text = xmalloc(count + 1);
                strncpy(job->text, *commandPtr, count);
                job->text[count] = '\0';
        }
@@ -729,35 +810,35 @@ static int parseCommand(char **commandPtr, struct job *job, int *isBg)
 }
 
 
-static int runCommand(struct job newJob, struct jobSet *jobList, int inBg)
+static int runCommand(struct job *newJob, struct jobSet *jobList, int inBg)
 {
        struct job *job;
        int i;
        int nextin, nextout;
        int pipefds[2];                         /* pipefd[0] is for reading */
        struct builtInCommand *x;
-#ifdef BB_FEATURE_STANDALONE_SHELL
+#ifdef BB_FEATURE_SH_STANDALONE_SHELL
        const struct BB_applet *a = applets;
 #endif
 
 
        nextin = 0, nextout = 1;
-       for (i = 0; i < newJob.numProgs; i++) {
-               if ((i + 1) < newJob.numProgs) {
+       for (i = 0; i < newJob->numProgs; i++) {
+               if ((i + 1) < newJob->numProgs) {
                        pipe(pipefds);
                        nextout = pipefds[1];
                } else {
                        nextout = 1;
                }
 
-               /* Match any built-ins here */
+               /* Check if the command matches any non-forking builtins */
                for (x = bltins; x->cmd; x++) {
-                       if (!strcmp(newJob.progs[i].argv[0], x->cmd)) {
-                               return (x->function(&newJob, jobList));
+                       if (!strcmp(newJob->progs[i].argv[0], x->cmd)) {
+                               return (x->function(newJob, jobList));
                        }
                }
 
-               if (!(newJob.progs[i].pid = fork())) {
+               if (!(newJob->progs[i].pid = fork())) {
                        signal(SIGTTOU, SIG_DFL);
 
                        if (nextin != 0) {
@@ -771,35 +852,37 @@ static int runCommand(struct job newJob, struct jobSet *jobList, int inBg)
                        }
 
                        /* explicit redirections override pipes */
-                       setupRedirections(newJob.progs + i);
+                       setupRedirections(newJob->progs + i);
 
-                       /* Match any built-ins here */
+                       /* Check if the command matches any of the other builtins */
                        for (x = bltins_forking; x->cmd; x++) {
-                               if (!strcmp(newJob.progs[i].argv[0], x->cmd)) {
-                                       exit (x->function(&newJob, jobList));
+                               if (!strcmp(newJob->progs[i].argv[0], x->cmd)) {
+                                       exit (x->function(newJob, jobList));
                                }
                        }
-#ifdef BB_FEATURE_STANDALONE_SHELL
-                       /* Handle busybox internals here */
+#ifdef BB_FEATURE_SH_STANDALONE_SHELL
+                       /* Check if the command matches any busybox internal commands here */
+                       /* TODO: Add matching when paths are appended (i.e. 'cat' currently
+                        * works, but '/bin/cat' doesn't ) */
                        while (a->name != 0) {
-                               if (strcmp(newJob.progs[i].argv[0], a->name) == 0) {
+                               if (strcmp(newJob->progs[i].argv[0], a->name) == 0) {
                                        int argc;
-                                       char** argv=newJob.progs[i].argv;
+                                       char** argv=newJob->progs[i].argv;
                                        for(argc=0;*argv!=NULL; argv++, argc++);
-                                       exit((*(a->main)) (argc, newJob.progs[i].argv));
+                                       exit((*(a->main)) (argc, newJob->progs[i].argv));
                                }
                                a++;
                        }
 #endif
 
-                       execvp(newJob.progs[i].argv[0], newJob.progs[i].argv);
-                       fatalError("sh: %s: %s\n", newJob.progs[i].argv[0],
+                       execvp(newJob->progs[i].argv[0], newJob->progs[i].argv);
+                       fatalError("%s: %s\n", newJob->progs[i].argv[0],
                                           strerror(errno));
                }
 
                /* put our child in the process group whose leader is the
                   first process in this pipe */
-               setpgid(newJob.progs[i].pid, newJob.progs[0].pid);
+               setpgid(newJob->progs[i].pid, newJob->progs[0].pid);
 
                if (nextin != 0)
                        close(nextin);
@@ -811,24 +894,24 @@ static int runCommand(struct job newJob, struct jobSet *jobList, int inBg)
                nextin = pipefds[0];
        }
 
-       newJob.pgrp = newJob.progs[0].pid;
+       newJob->pgrp = newJob->progs[0].pid;
 
        /* find the ID for the job to use */
-       newJob.jobId = 1;
+       newJob->jobId = 1;
        for (job = jobList->head; job; job = job->next)
-               if (job->jobId >= newJob.jobId)
-                       newJob.jobId = job->jobId + 1;
+               if (job->jobId >= newJob->jobId)
+                       newJob->jobId = job->jobId + 1;
 
        /* add the job to the list of running jobs */
        if (!jobList->head) {
-               job = jobList->head = malloc(sizeof(*job));
+               job = jobList->head = xmalloc(sizeof(*job));
        } else {
                for (job = jobList->head; job->next; job = job->next);
-               job->next = malloc(sizeof(*job));
+               job->next = xmalloc(sizeof(*job));
                job = job->next;
        }
 
-       *job = newJob;
+       *job = *newJob;
        job->next = NULL;
        job->runningProgs = job->numProgs;
        job->stoppedProgs = 0;
@@ -837,12 +920,13 @@ static int runCommand(struct job newJob, struct jobSet *jobList, int inBg)
                /* we don't wait for background jobs to return -- append it 
                   to the list of backgrounded jobs and leave it alone */
                printf("[%d] %d\n", job->jobId,
-                          newJob.progs[newJob.numProgs - 1].pid);
+                          newJob->progs[newJob->numProgs - 1].pid);
        } else {
                jobList->fg = job;
 
                /* move the new process group into the foreground */
-               if (tcsetpgrp(0, newJob.pgrp))
+               /* suppress messages when run from /linuxrc mag@sysgo.de */
+               if (tcsetpgrp(0, newJob->pgrp) && errno != ENOTTY)
                        perror("tcsetpgrp");
        }
 
@@ -873,7 +957,7 @@ static int setupRedirections(struct childProgram *prog)
                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!) */
-                       fprintf(stderr, "error opening %s: %s\n", redir->filename,
+                       errorMsg("error opening %s: %s\n", redir->filename,
                                        strerror(errno));
                        return 1;
                }
@@ -894,10 +978,14 @@ static int busy_loop(FILE * input)
        char *nextCommand = NULL;
        struct jobSet jobList = { NULL, NULL };
        struct job newJob;
+       pid_t  parent_pgrp;
        int i;
        int status;
        int inBg;
 
+       /* save current owner of TTY so we can restore it on exit */
+       parent_pgrp = tcgetpgrp(0);
+
        command = (char *) calloc(BUFSIZ, sizeof(char));
 
        /* don't pay any attention to this signal; it just confuses 
@@ -917,9 +1005,11 @@ static int busy_loop(FILE * input)
                                nextCommand = command;
                        }
 
-                       if (!parseCommand(&nextCommand, &newJob, &inBg) &&
+                       if (!parseCommand(&nextCommand, &newJob, &jobList, &inBg) &&
                                newJob.numProgs) {
-                               runCommand(newJob, &jobList, inBg);
+                               runCommand(&newJob, &jobList, inBg);
+                       } else {
+                               nextCommand=NULL;
                        }
                } else {
                        /* a job is running in the foreground; wait for it */
@@ -939,10 +1029,6 @@ static int busy_loop(FILE * input)
 
                                        removeJob(&jobList, jobList.fg);
                                        jobList.fg = NULL;
-
-                                       /* move the shell to the foreground */
-                                       if (tcsetpgrp(0, getpid()))
-                                               perror("tcsetpgrp");
                                }
                        } else {
                                /* the child was stopped */
@@ -958,13 +1044,22 @@ static int busy_loop(FILE * input)
 
                        if (!jobList.fg) {
                                /* move the shell to the foreground */
-                               if (tcsetpgrp(0, getpid()))
-                                       perror("tcsetpgrp");
+                               /* suppress messages when run from /linuxrc mag@sysgo.de */
+                               if (tcsetpgrp(0, getpid()) && errno != ENOTTY)
+                                       perror("tcsetpgrp"); 
                        }
                }
        }
        free(command);
 
+       /* return controlling TTY back to parent process group before exiting */
+       if (tcsetpgrp(0, parent_pgrp))
+               perror("tcsetpgrp");
+
+       /* return exit status if called with "-c" */
+       if (input == NULL && WIFEXITED(status))
+               return WEXITSTATUS(status);
+       
        return 0;
 }
 
@@ -973,11 +1068,12 @@ int shell_main(int argc, char **argv)
 {
        FILE *input = stdin;
 
-       if (argc > 2) {
-               usage(shell_usage);
-       }
        /* initialize the cwd */
-       getcwd(cwd, sizeof(cwd));
+       cwd = (char *) calloc(BUFSIZ, sizeof(char));
+       if (cwd == 0) {
+               fatalError("out of memory\n");
+       }
+       getcwd(cwd, sizeof(char)*BUFSIZ);
 
 #ifdef BB_FEATURE_SH_COMMAND_EDITING
        cmdedit_init();
@@ -986,20 +1082,43 @@ int shell_main(int argc, char **argv)
 #endif
 
        //if (argv[0] && argv[0][0] == '-') {
-       //      shell_source("/etc/profile");
+       //      builtin_source("/etc/profile");
        //}
 
        if (argc < 2) {
                fprintf(stdout, "\n\nBusyBox v%s (%s) Built-in shell\n", BB_VER, BB_BT);
                fprintf(stdout, "Enter 'help' for a list of built-in commands.\n\n");
        } else {
-               if (*argv[1]=='-') {
-                       usage("sh\n\nlash -- the BusyBox LAme SHell (command interpreter)\n");
+               if (argv[1][0]=='-' && argv[1][1]=='c') {
+                       int i;
+                       local_pending_command = (char *) calloc(BUFSIZ, sizeof(char));
+                       if (local_pending_command == 0) {
+                               fatalError("out of memory\n");
+                       }
+                       for(i=2; i<argc; i++)
+                       {
+                               if (strlen(local_pending_command) + strlen(argv[i]) >= BUFSIZ) {
+                                       local_pending_command = realloc(local_pending_command, 
+                                                       strlen(local_pending_command) + strlen(argv[i]));
+                                       if (local_pending_command==NULL) 
+                                         fatalError("commands for -c option too long\n");
+                               }
+                               strcat(local_pending_command, argv[i]);
+                               if ( (i + 1) < argc)
+                                 strcat(local_pending_command, " ");
+                       }
+                       input = NULL;
+                         
                }
-               input = fopen(argv[1], "r");
-               if (!input) {
-                       fatalError("sh: Couldn't open file '%s': %s\n", argv[1],
-                                          strerror(errno));
+               else if (argv[1][0]=='-') {
+                       usage(shell_usage);
+               }
+               else {
+                       input = fopen(argv[1], "r");
+                       if (!input) {
+                               fatalError("Couldn't open file '%s': %s\n", argv[1],
+                                                  strerror(errno));
+                       }
                }
        }