Support disabling pipe and redirect support

1 files changed, 67 insertions, 40 deletions

diff --git a/shell/lash.c b/shell/lash.c
index 1fcd63bdf..3675d21df 100644
--- a/shell/lash.c
+++ b/shell/lash.c
@@ -56,14 +56,18 @@
 #include <glob.h>
 #define expand_t        glob_t
 
+/* Always enable for the moment... */
+#define CONFIG_LASH_PIPE_N_REDIRECTS
 
 static const int MAX_READ = 128;        /* size of input buffer for `read' builtin */
 #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
 
 
+#ifdef CONFIG_LASH_PIPE_N_REDIRECTS
 enum redir_type { REDIRECT_INPUT, REDIRECT_OVERWRITE,
         REDIRECT_APPEND
 };
+#endif
 
 static const unsigned int DEFAULT_CONTEXT=0x1;
 static const unsigned int IF_TRUE_CONTEXT=0x2;
@@ -71,25 +75,28 @@ static const unsigned int IF_FALSE_CONTEXT=0x4;
 static const unsigned int THEN_EXP_CONTEXT=0x8;
 static const unsigned int ELSE_EXP_CONTEXT=0x10;
 
-
-struct jobset {
-        struct job *head;                       /* head of list of running jobs */
-        struct job *fg;                         /* current foreground job */
-};
-
+#ifdef CONFIG_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 */
-        struct redir_struct *redirects; /* I/O redirects */
         int is_stopped;                         /* is the program currently running? */
         struct job *family;                     /* pointer back to the child's parent job */
+#ifdef CONFIG_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 {
@@ -514,8 +521,10 @@ static void free_job(struct job *cmd)
 
         for (i = 0; i < cmd->num_progs; i++) {
                 free(cmd->progs[i].argv);
+#ifdef CONFIG_LASH_PIPE_N_REDIRECTS
                 if (cmd->progs[i].redirects)
                         free(cmd->progs[i].redirects);
+#endif
         }
         free(cmd->progs);
         free(cmd->text);
@@ -548,7 +557,7 @@ static void remove_job(struct jobset *j_list, struct job *job)
         free(job);
 }
 
-/* Checks to see if any background processes have exited -- if they 
+/* 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)
 {
@@ -593,7 +602,7 @@ static void checkjobs(struct jobset *j_list)
                                 printf(JOB_STATUS_FORMAT, job->jobid, "Stopped",
                                            job->text);
                         }
-#endif  
+#endif
                 }
         }
 
@@ -601,6 +610,7 @@ static void checkjobs(struct jobset *j_list)
                 bb_perror_msg("waitpid");
 }
 
+#ifdef CONFIG_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[])
@@ -656,6 +666,15 @@ static void restore_redirects(int squirrel[])
                 }
         }
 }
+#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)
 {
@@ -665,7 +684,7 @@ static inline void cmdedit_set_initial_prompt(void)
         PS1 = getenv("PS1");
         if(PS1==0)
                 PS1 = "\\w \\$ ";
-#endif  
+#endif
 }
 
 static inline void setup_prompt_string(char **prompt_str)
@@ -682,7 +701,7 @@ static inline void setup_prompt_string(char **prompt_str)
         }
 #else
         *prompt_str = (shell_context==0)? PS1 : PS2;
-#endif  
+#endif
 }
 
 static int get_command(FILE * source, char *command)
@@ -761,7 +780,7 @@ char * strsep_space( char *string, int * ix)
                 (*ix)++;
         }
 
-        /* Find the end of any whitespace trailing behind 
+        /* Find the end of any whitespace trailing behind
          * the token and let that be part of the token */
         while( string && string[*ix] && isspace(string[*ix]) ) {
                 (*ix)++;
@@ -774,7 +793,7 @@ char * strsep_space( char *string, int * ix)
 
         token = xmalloc(*ix+1);
         token[*ix] = '\0';
-        strncpy(token, string,  *ix); 
+        strncpy(token, string,  *ix);
 
         return token;
 }
@@ -789,10 +808,10 @@ static int expand_arguments(char *command)
         int flags = GLOB_NOCHECK
 #ifdef GLOB_BRACE
                 | GLOB_BRACE
-#endif  
+#endif
 #ifdef GLOB_TILDE
                 | GLOB_TILDE
-#endif  
+#endif
                 ;
 
         /* get rid of the terminating \n */
@@ -817,7 +836,7 @@ static int expand_arguments(char *command)
          * we write stuff into the original (in a minute) */
         cmd = cmd_copy = bb_xstrdup(command);
         *command = '\0';
-        for (ix = 0, tmpcmd = cmd; 
+        for (ix = 0, tmpcmd = cmd;
                         (tmpcmd = strsep_space(cmd, &ix)) != NULL; cmd += ix, ix=0) {
                 if (*tmpcmd == '\0')
                         break;
@@ -832,7 +851,7 @@ static int expand_arguments(char *command)
                         return FALSE;
                 } else if (retval != 0) {
                         /* Some other error.  GLOB_NOMATCH shouldn't
-                         * happen because of the GLOB_NOCHECK flag in 
+                         * happen because of the GLOB_NOCHECK flag in
                          * the glob call. */
                         bb_error_msg("syntax error");
                         return FALSE;
@@ -856,7 +875,7 @@ static int expand_arguments(char *command)
         free(cmd_copy);
         trim(command);
 
-        /* Now do the shell variable substitutions which 
+        /* Now do the shell variable substitutions which
          * wordexp can't do for us, namely $? and $! */
         src = command;
         while((dst = strchr(src,'$')) != NULL){
@@ -946,21 +965,25 @@ static int expand_arguments(char *command)
 
 /* 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 
+   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, *chptr;
+        char *src, *buf;
         int argc_l = 0;
         int done = 0;
         int argv_alloced;
-        int i, saw_quote = 0;
+        int saw_quote = 0;
         char quote = '\0';
         int count;
         struct child_prog *prog;
+#ifdef CONFIG_LASH_PIPE_N_REDIRECTS
+        int i;
+        char *chptr;
+#endif
 
         /* skip leading white space */
         while (**command_ptr && isspace(**command_ptr))
@@ -976,21 +999,23 @@ static int parse_command(char **command_ptr, struct job *job, int *inbg)
         job->num_progs = 1;
         job->progs = xmalloc(sizeof(*job->progs));
 
-        /* We set the argv elements to point inside of this string. The 
+        /* 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 
+           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 = xcalloc(2*strlen(*command_ptr) + 1, sizeof(char));
         job->text = NULL;
 
         prog = job->progs;
         prog->num_redirects = 0;
-        prog->redirects = NULL;
         prog->is_stopped = 0;
         prog->family = job;
+#ifdef CONFIG_LASH_PIPE_N_REDIRECTS
+        prog->redirects = NULL;
+#endif
 
         argv_alloced = 5;
         prog->argv = xmalloc(sizeof(*prog->argv) * argv_alloced);
@@ -1046,6 +1071,7 @@ static int parse_command(char **command_ptr, struct job *job, int *inbg)
                                         done = 1;
                                 break;
 
+#ifdef CONFIG_LASH_PIPE_N_REDIRECTS
                         case '>':                       /* redirects */
                         case '<':
                                 i = prog->num_redirects++;
@@ -1143,6 +1169,7 @@ static int parse_command(char **command_ptr, struct job *job, int *inbg)
                                 src--;                  /* we'll ++ it at the end of the loop */
 
                                 break;
+#endif
 
                         case '&':                       /* background */
                                 *inbg = 1;
@@ -1189,7 +1216,7 @@ static int parse_command(char **command_ptr, struct job *job, int *inbg)
         }
 
         *command_ptr = return_command;
-        
+
         return 0;
 }
 
@@ -1236,7 +1263,7 @@ static int pseudo_exec(struct child_prog *child)
 
 #ifdef CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN
         /* If you enable CONFIG_FEATURE_SH_APPLETS_ALWAYS_WIN, then
-         * if you run /bin/cat, it will use BusyBox cat even if 
+         * if you run /bin/cat, it will use BusyBox cat even if
          * /bin/cat exists on the filesystem and is _not_ busybox.
          * Some systems want this, others do not.  Choose wisely.  :-)
          */
@@ -1254,7 +1281,7 @@ static int pseudo_exec(struct child_prog *child)
 
         execvp(child->argv[0], child->argv);
 
-        /* Do not use bb_perror_msg_and_die() here, since we must not 
+        /* Do not use bb_perror_msg_and_die() here, since we must not
          * call exit() but should call _exit() instead */
         fprintf(stderr, "%s: %m\n", child->argv[0]);
         _exit(EXIT_FAILURE);
@@ -1286,7 +1313,7 @@ static void insert_job(struct job *newjob, int inbg)
         thejob->stopped_progs = 0;
 
         if (inbg) {
-                /* we don't wait for background thejobs to return -- append it 
+                /* 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);
@@ -1336,8 +1363,8 @@ static int run_command(struct job *newjob, int inbg, int outpipe[2])
                 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;
+                                        int squirrel[] = {-1, -1, -1};
                                         setup_redirects(child, squirrel);
                                         rcode = x->function(child);
                                         restore_redirects(squirrel);
@@ -1347,9 +1374,9 @@ static int run_command(struct job *newjob, int inbg, int outpipe[2])
                 }
 
 #if !defined(__UCLIBC__) || defined(__UCLIBC_HAS_MMU__)
-                if (!(child->pid = fork())) 
+                if (!(child->pid = fork()))
 #else
-                if (!(child->pid = vfork())) 
+                if (!(child->pid = vfork()))
 #endif
                 {
                         /* Set the handling for job control signals back to the default.  */
@@ -1394,7 +1421,7 @@ static int run_command(struct job *newjob, int inbg, int outpipe[2])
                 if (nextout != 1)
                         close(nextout);
 
-                /* If there isn't another process, nextin is garbage 
+                /* If there isn't another process, nextin is garbage
                    but it doesn't matter */
                 nextin = pipefds[0];
         }
@@ -1446,7 +1473,7 @@ static int busy_loop(FILE * input)
                         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", 
+                                debug_printf( "job=%p fed to run_command by busy_loop()'\n",
                                                 &newjob);
                                 run_command(&newjob, inbg, pipefds);
                         }
@@ -1495,7 +1522,7 @@ static int busy_loop(FILE * input)
                                 /* 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"); 
+                                        bb_perror_msg("tcsetpgrp");
                         }
                 }
         }
@@ -1508,7 +1535,7 @@ static int busy_loop(FILE * input)
         /* return exit status if called with "-c" */
         if (input == NULL && WIFEXITED(status))
                 return WEXITSTATUS(status);
-        
+
         return 0;
 }
 
@@ -1534,7 +1561,7 @@ void free_memory(void)
 static void setup_job_control(void)
 {
         int status;
-        
+
         /* Loop until we are in the foreground.  */
         while ((status = tcgetpgrp (shell_terminal)) >= 0) {
                 if (status == (shell_pgrp = getpgrp ())) {
@@ -1580,7 +1607,7 @@ int lash_main(int argc_l, char **argv_l)
                 prof_input = fopen("/etc/profile", "r");
                 if (prof_input) {
                         int tmp_fd = fileno(prof_input);
-                        mark_open(tmp_fd);      
+                        mark_open(tmp_fd);
                         /* Now run the file */
                         busy_loop(prof_input);
                         fclose(prof_input);
@@ -1644,6 +1671,6 @@ int lash_main(int argc_l, char **argv_l)
 #else
         PS1 = NULL;
 #endif
-        
+
         return (busy_loop(input));
 }