Add in a shell tagline (per lash/hush behavior) to make it easier

to know which shell is in use.  Add in 'help' to list available
builtins, and fixup msh so it can do STANDALONE_SHELL.
 -Erik


git-svn-id: svn://busybox.net/trunk/busybox@3025 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 98 insertions, 30 deletions

diff --git a/msh.c b/msh.c
index 66c3d54d3..e85d6ff8f 100644
--- a/msh.c
+++ b/msh.c
@@ -497,6 +497,7 @@ static struct op **find1case (struct op *t, char *w );
 static struct op *findcase (struct op *t, char *w );
 static void brkset(struct brkcon *bc );
 static int dolabel(void);
+static int dohelp(void);
 static int dochdir(struct op *t );
 static int doshift(struct op *t );
 static int dologin(struct op *t );
@@ -592,30 +593,31 @@ static struct res restab[] = {
 };
 
 
-struct  builtin {
-        char *command;
-        int      (*fn)();
+struct builtincmd {
+        const char *name;
+        int (*builtinfunc)();
 };
-static struct   builtin builtin[] = {
+static const struct     builtincmd      builtincmds[] = {
+    {".",               dodot},
     {":",               dolabel},
-    {"cd",              dochdir},
-    {"shift",   doshift},
-    {"exec",    doexec},
-    {"wait",    dowait},
-    {"read",    doread},
-    {"eval",    doeval},
-    {"trap",    dotrap},
     {"break",   dobreak},
+    {"cd",              dochdir},
     {"continue",docontinue},
+    {"eval",    doeval},
+    {"exec",    doexec},
     {"exit",    doexit},
     {"export",  doexport},
-    {"readonly",doreadonly},
-    {"set",             doset},
-    {".",               dodot},
-    {"umask",   doumask},
+    {"help",    dohelp},
     {"login",   dologin},
     {"newgrp",  dologin},
+    {"read",    doread},
+    {"readonly",doreadonly},
+    {"set",             doset},
+    {"shift",   doshift},
     {"times",   dotimes},
+    {"trap",    dotrap},
+    {"umask",   doumask},
+    {"wait",    dowait},
     {0,0}
 };
 
@@ -731,14 +733,18 @@ extern int shell_main(int argc, char **argv)
                 setval(ifs, " \t\n");
 
         prompt = lookup("PS1");
+#ifdef BB_FEATURE_SH_FANCY_PROMPT
         if (prompt->value == null)
+#endif
                 setval(prompt, "$ ");
         if (geteuid() == 0) {
                 setval(prompt, "# ");
                 prompt->status &= ~EXPORT;
         }
         cprompt = lookup("PS2");
+#ifdef BB_FEATURE_SH_FANCY_PROMPT
         if (cprompt->value == null)
+#endif
                 setval(cprompt, "> ");
 
         iof = filechar;
@@ -794,8 +800,11 @@ extern int shell_main(int argc, char **argv)
         setdash();
         if (e.iop < iostack) {
                 PUSHIO(afile, 0, iof);
-                if (isatty(0) && isatty(1) && !cflag)
+                if (isatty(0) && isatty(1) && !cflag) {
                         interactive++;
+                        printf( "\n\n" BB_BANNER " Built-in shell (msh)\n");
+                        printf( "Enter 'help' for a list of built-in commands.\n\n");
+                }
         }
         signal(SIGQUIT, qflag);
         if (name && name[0] == '-') {
@@ -2314,14 +2323,14 @@ int act;
         switch(t->type) {
         case TPAREN:
         case TCOM:
-            {
-                int child;
-                rv = forkexec(t, pin, pout, act, wp, &child);
-                if (child) {
-                        exstat = rv;
-                        leave();
+                {
+                        int child;
+                        rv = forkexec(t, pin, pout, act, wp, &child);
+                        if (child) {
+                                exstat = rv;
+                                leave();
+                        }
                 }
-            }
                 break;
 
         case TPIPE:
@@ -2828,6 +2837,21 @@ char *c, **v, **envp;
         register char *sp, *tp;
         int eacces = 0, asis = 0;
 
+#ifdef BB_FEATURE_SH_STANDALONE_SHELL
+        char *name = c;
+#ifdef BB_FEATURE_SH_APPLETS_ALWAYS_WIN
+        name = get_last_path_component(name);
+#endif
+        optind = 1;
+        if (find_applet_by_name(name)) {
+                /* We have to exec here since we vforked.  Running 
+                 * run_applet_by_name() won't work and bad things
+                 * will happen. */
+                execve("/proc/self/exe", v, envp);
+                execve("busybox", v, envp);
+        }
+#endif
+
         sp = any('/', c)? "": path->value;
         asis = *sp == '\0';
         while (asis || *sp != '\0') {
@@ -2842,6 +2866,8 @@ char *c, **v, **envp;
                         *tp++ = '/';
                 for (i = 0; (*tp++ = c[i++]) != '\0';)
                         ;
+
+                fprintf(stderr, "calling exec\n");
                 execve(e.linep, v, envp);
                 switch (errno) {
                 case ENOEXEC:
@@ -2917,6 +2943,49 @@ int (*f)();
  * built-in commands: doX
  */
 
+static int dohelp()
+{
+        int col;
+        const struct builtincmd *x;
+
+        printf("\nBuilt-in commands:\n");
+        printf("-------------------\n");
+
+        for (col=0, x = builtincmds; x->builtinfunc != NULL; x++) {
+                if (!x->name)
+                        continue;
+                col += printf("%s%s", ((col == 0) ? "\t" : " "), x->name);
+                if (col > 60) {
+                        printf("\n");
+                        col = 0;
+                }
+        }
+#ifdef BB_FEATURE_SH_STANDALONE_SHELL
+        {
+                int i;
+                const struct BB_applet *applet;
+                extern const struct BB_applet applets[];
+                extern const size_t NUM_APPLETS;
+
+                for (i=0, applet = applets; i < NUM_APPLETS; applet++, i++) {
+                        if (!applet->name)
+                                continue;
+                
+                        col += printf("%s%s", ((col == 0) ? "\t" : " "), 
+                                        applet->name);
+                        if (col > 60) {
+                                printf("\n");
+                                col = 0;
+                        }
+                }
+        }
+#endif
+        printf("\n\n");
+        return EXIT_SUCCESS;
+}
+
+
+
 static int
 dolabel()
 {
@@ -3341,7 +3410,6 @@ int out;
 /*
  * Copyright (c) 1999 Herbert Xu <herbert@debian.org>
  * This file contains code for the times builtin.
- * $Id: msh.c,v 1.1 2001/06/29 04:57:14 andersen Exp $
  */
 static int dotimes ()
 {
@@ -3362,14 +3430,14 @@ static int dotimes ()
 }
 
 
-static int (*inbuilt(s))()
-register char *s;
+static int (*inbuilt(char *s))()
 {
-        register struct builtin *bp;
+        const struct builtincmd *bp;
+
+        for (bp = builtincmds; bp->name != NULL; bp++)
+                if (strcmp(bp->name, s) == 0)
+                        return(bp->builtinfunc);
 
-        for (bp = builtin; bp->command != NULL; bp++)
-                if (strcmp(bp->command, s) == 0)
-                        return(bp->fn);
         return((int(*)())NULL);
 }