hush: fix job control with eval /bin/external_prog

hush: fix parsing of unterminated "str with no EOL
hush: improved make_string() (smaller, faster, needs less RAM)
hush: renamed several functions

3 files changed, 96 insertions, 92 deletions

diff --git a/shell/hush.c b/shell/hush.c
index aab6ff3a3..1545b041f 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -117,6 +117,9 @@ extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
 #define DEBUG_EXPAND 1
 #endif
 
+/* Keep unconditionally on for now */
+#define ENABLE_HUSH_DEBUG 1
+
 #ifndef debug_printf_clean
 /* broken, of course, but OK for testing */
 static const char *indenter(int i)
@@ -497,13 +500,12 @@ static int process_command_subs(o_string *dest, struct p_context *ctx, struct in
 #endif
 static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
 static const char *lookup_param(const char *src);
-static char *make_string(char **inp);
 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
 static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, const char *end_trigger);
 /*   setup: */
-static int parse_stream_outer(struct in_str *inp, int parse_flag);
-static int parse_string_outer(const char *s, int parse_flag);
-static int parse_file_outer(FILE *f);
+static int parse_and_run_stream(struct in_str *inp, int parse_flag);
+static int parse_and_run_string(const char *s, int parse_flag);
+static int parse_and_run_file(FILE *f);
 /*   job management: */
 static int checkjobs(struct pipe* fg_pipe);
 #if ENABLE_HUSH_JOB
@@ -515,9 +517,11 @@ static void delete_finished_bg_job(struct pipe *pi);
 int checkjobs_and_fg_shell(struct pipe* fg_pipe); /* never called */
 #endif
 /*     local variable support */
-static char **expand_variables_to_list(char **argv);
+static char **expand_strvec_to_strvec(char **argv);
+/* used for eval */
+static char *expand_strvec_to_string(char **argv);
 /* used for expansion of right hand of assignments */
-static char *expand_variables_to_string(const char *str);
+static char *expand_string_to_string(const char *str);
 static const char *get_local_var(const char *var);
 static int set_local_var(const char *s, int flg_export);
 static void unset_local_var(const char *name);
@@ -716,12 +720,11 @@ static const char *set_cwd(void)
 /* built-in 'eval' handler */
 static int builtin_eval(char **argv)
 {
-        char *str = NULL;
         int rcode = EXIT_SUCCESS;
 
         if (argv[1]) {
-                str = make_string(argv + 1);
-                parse_string_outer(str, PARSEFLAG_EXIT_FROM_LOOP |
+                char *str = expand_strvec_to_string(argv + 1);
+                parse_and_run_string(str, PARSEFLAG_EXIT_FROM_LOOP |
                                         PARSEFLAG_SEMICOLON);
                 free(str);
                 rcode = last_return_code;
@@ -732,9 +735,9 @@ static int builtin_eval(char **argv)
 /* built-in 'cd <path>' handler */
 static int builtin_cd(char **argv)
 {
-        char *newdir;
+        const char *newdir;
         if (argv[1] == NULL)
-                newdir = getenv("HOME");
+                newdir = getenv("HOME") ? : "/";
         else
                 newdir = argv[1];
         if (chdir(newdir)) {
@@ -999,7 +1002,7 @@ static int builtin_source(char **argv)
          * (pointer only is OK!) on this stack frame,
          * set global_argv=argv+1, recurse, and restore. */
         mark_open(fileno(input));
-        status = parse_file_outer(input);
+        status = parse_and_run_file(input);
         mark_closed(fileno(input));
         fclose(input);
         return status;
@@ -1146,12 +1149,10 @@ static void get_user_input(struct in_str *i)
 
         prompt_str = setup_prompt_string(i->promptmode);
 #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)
-         */
+        /* 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) */
         r = read_line_input(prompt_str, user_input_buf, BUFSIZ-1, line_input_state);
         i->eof_flag = (r < 0);
         if (i->eof_flag) { /* EOF/error detected */
@@ -1343,8 +1344,8 @@ static void pseudo_exec_argv(char **argv)
                 debug_printf_exec("pid %d environment modification: %s\n",
                                 getpid(), argv[i]);
 // FIXME: vfork case??
-                p = expand_variables_to_string(argv[i]);
-                putenv(p == argv[i] ? xstrdup(p) : p);
+                p = expand_string_to_string(argv[i]);
+                putenv(p);
         }
         argv += i;
         /* If a variable is assigned in a forest, and nobody listens,
@@ -1354,7 +1355,7 @@ static void pseudo_exec_argv(char **argv)
                 _exit(EXIT_SUCCESS);
         }
 
-        argv = expand_variables_to_list(argv);
+        argv = expand_strvec_to_strvec(argv);
 
         /*
          * Check if the command matches any of the builtins.
@@ -1652,8 +1653,8 @@ static int checkjobs_and_fg_shell(struct pipe* fg_pipe)
         pid_t p;
         int rcode = checkjobs(fg_pipe);
         /* Job finished, move the shell to the foreground */
-        p = getpgid(0);
-        debug_printf("fg'ing ourself: getpgid(0)=%d\n", (int)p);
+        p = getpgid(0); /* pgid of our process */
+        debug_printf_jobs("fg'ing ourself: getpgid(0)=%d\n", (int)p);
         if (tcsetpgrp(interactive_fd, p) && errno != ENOTTY)
                 bb_perror_msg("tcsetpgrp-4a");
         return rcode;
@@ -1675,6 +1676,9 @@ static int checkjobs_and_fg_shell(struct pipe* fg_pipe)
  * subshell, when that is in fact necessary.  The subshell process
  * now has its stdout directed to the input of the appropriate pipe,
  * so this routine is noticeably simpler.
+ *
+ * Returns -1 only if started some children. IOW: we have to
+ * mask out retvals of builtins etc with 0xff!
  */
 static int run_pipe_real(struct pipe *pi)
 {
@@ -1710,7 +1714,7 @@ static int run_pipe_real(struct pipe *pi)
                 rcode = run_list_real(child->group);
                 restore_redirects(squirrel);
                 debug_printf_exec("run_pipe_real return %d\n", rcode);
-                return rcode;
+                return rcode; // do we need to add '... & 0xff' ?
         }
 
         if (single_fg && child->argv != NULL) {
@@ -1739,21 +1743,16 @@ static int run_pipe_real(struct pipe *pi)
                                         export_me = 1;
                                 }
                                 free(name);
-                                p = expand_variables_to_string(argv[i]);
+                                p = expand_string_to_string(argv[i]);
                                 set_local_var(p, export_me);
-                                if (p != argv[i])
-                                        free(p);
+                                free(p);
                         }
                         return EXIT_SUCCESS;   /* don't worry about errors in set_local_var() yet */
                 }
                 for (i = 0; is_assignment(argv[i]); i++) {
-                        p = expand_variables_to_string(argv[i]);
-                        if (p != argv[i]) {
-                                //sp: child->sp--;
-                                putenv(p);
-                        } else {
-                                putenv(xstrdup(p));
-                        }
+                        p = expand_string_to_string(argv[i]);
+                        //sp: child->sp--;
+                        putenv(p);
                 }
                 for (x = bltins; x->cmd; x++) {
                         if (strcmp(argv[i], x->cmd) == 0) {
@@ -1770,8 +1769,8 @@ static int run_pipe_real(struct pipe *pi)
                                 setup_redirects(child, squirrel);
                                 debug_printf_exec(": builtin '%s' '%s'...\n", x->cmd, argv[i+1]);
                                 //sp: if (child->sp) /* btw we can do it unconditionally... */
-                                argv_expanded = expand_variables_to_list(argv + i);
-                                rcode = x->function(argv_expanded);
+                                argv_expanded = expand_strvec_to_strvec(argv + i);
+                                rcode = x->function(argv_expanded) & 0xff;
                                 free(argv_expanded);
                                 restore_redirects(squirrel);
                                 debug_printf_exec("run_pipe_real return %d\n", rcode);
@@ -1786,9 +1785,9 @@ static int run_pipe_real(struct pipe *pi)
                                 save_nofork_data(&nofork_save);
                                 argv_expanded = argv + i;
                                 //sp: if (child->sp)
-                                argv_expanded = expand_variables_to_list(argv + i);
+                                argv_expanded = expand_strvec_to_strvec(argv + i);
                                 debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", argv_expanded[0], argv_expanded[1]);
-                                rcode = run_nofork_applet_prime(&nofork_save, a, argv_expanded);
+                                rcode = run_nofork_applet_prime(&nofork_save, a, argv_expanded) & 0xff;
                                 free(argv_expanded);
                                 restore_redirects(squirrel);
                                 debug_printf_exec("run_pipe_real return %d\n", rcode);
@@ -1832,7 +1831,7 @@ static int run_pipe_real(struct pipe *pi)
                         /* Every child adds itself to new process group
                          * with pgid == pid of first child in pipe */
 #if ENABLE_HUSH_JOB
-                        if (interactive_fd) {
+                        if (run_list_level == 1 && interactive_fd) {
                                 /* Don't do pgrp restore anymore on fatal signals */
                                 set_fatal_sighandler(SIG_DFL);
                                 if (pi->pgrp < 0) /* true for 1st process only */
@@ -2078,7 +2077,7 @@ static int run_list_real(struct pipe *pi)
                                 if (!pi->next->progs->argv)
                                         continue;
                                 /* create list of variable values */
-                                for_list = expand_variables_to_list(pi->next->progs->argv);
+                                for_list = expand_strvec_to_strvec(pi->next->progs->argv);
                                 for_lcur = for_list;
                                 for_varname = pi->progs->argv[0];
                                 pi->progs->argv[0] = NULL;
@@ -2122,24 +2121,24 @@ static int run_list_real(struct pipe *pi)
                          * of run_pipe_real(), and we don't need to wait for anything. */
                 } else if (pi->followup == PIPE_BG) {
                         /* What does bash do with attempts to background builtins? */
-
                         /* Even bash 3.2 doesn't do that well with nested bg:
                          * try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
-                         * I'm considering NOT treating inner bgs as jobs -
-                         * thus maybe "if (run_list_level == 1 && pi->followup == PIPE_BG)"
-                         * above? */
+                         * I'm NOT treating inner &'s as jobs */
 #if ENABLE_HUSH_JOB
-                        insert_bg_job(pi);
+                        if (run_list_level == 1) 
+                                insert_bg_job(pi);
 #endif
                         rcode = EXIT_SUCCESS;
                 } else {
 #if ENABLE_HUSH_JOB
-                        /* Paranoia, just "interactive_fd" should be enough */
+                        /* Paranoia, just "interactive_fd" should be enough? */
                         if (run_list_level == 1 && interactive_fd) {
+                                /* waits for completion, then fg's main shell */
                                 rcode = checkjobs_and_fg_shell(pi);
                         } else
 #endif
                         {
+                                /* this one just waits for completion */
                                 rcode = checkjobs(pi);
                         }
                         debug_printf_exec(": checkjobs returned %d\n", rcode);
@@ -2343,7 +2342,7 @@ static int xglob(o_string *dest, int flags, glob_t *pglob)
         return gr;
 }
 
-/* expand_variables_to_list() takes a list of strings, expands
+/* expand_strvec_to_strvec() takes a list of strings, expands
  * all variable references within and returns a pointer to
  * a list of expanded strings, possibly with larger number
  * of strings. (Think VAR="a b"; echo $VAR).
@@ -2629,29 +2628,51 @@ static char **expand_variables(char **argv, char or_mask)
                 debug_printf_expand("used_space=%d\n", pos - (char*)list);
         }
 #endif
-        /* To be removed / made conditional later. */
-        if (pos - (char*)list > len)
-                bb_error_msg_and_die("BUG in varexp");
+        if (ENABLE_HUSH_DEBUG)
+                if (pos - (char*)list > len)
+                        bb_error_msg_and_die("BUG in varexp");
         return list;
 }
 
-static char **expand_variables_to_list(char **argv)
+static char **expand_strvec_to_strvec(char **argv)
 {
         return expand_variables(argv, 0);
 }
 
-static char *expand_variables_to_string(const char *str)
+static char *expand_string_to_string(const char *str)
 {
         char *argv[2], **list;
 
         argv[0] = (char*)str;
         argv[1] = NULL;
         list = expand_variables(argv, 0x80); /* 0x80: make one-element expansion */
-        /* To be removed / made conditional later. */
-        if (!list[0] || list[1])
-                bb_error_msg_and_die("BUG in varexp");
+        if (ENABLE_HUSH_DEBUG)
+                if (!list[0] || list[1])
+                        bb_error_msg_and_die("BUG in varexp2");
         /* actually, just move string 2*sizeof(char*) bytes back */
         strcpy((char*)list, list[0]);
+        debug_printf_expand("string_to_string='%s'\n", (char*)list);
+        return (char*)list;
+}
+
+static char* expand_strvec_to_string(char **argv)
+{
+        char **list;
+
+        list = expand_variables(argv, 0x80);
+        /* Convert all NULs to spaces */
+        if (list[0]) {
+                int n = 1;
+                while (list[n]) {
+                        if (ENABLE_HUSH_DEBUG)
+                                if (list[n-1] + strlen(list[n-1]) + 1 != list[n])
+                                        bb_error_msg_and_die("BUG in varexp3");
+                        list[n][-1] = ' '; /* TODO: or to ifs[0]? */
+                        n++;
+                }
+        }
+        strcpy((char*)list, list[0]);
+        debug_printf_expand("strvec_to_string='%s'\n", (char*)list);
         return (char*)list;
 }
 
@@ -2713,9 +2734,9 @@ static int set_local_var(const char *s, int flg_export)
         }
 
         cur = xzalloc(sizeof(*cur));
+        /*cur->next = 0;*/
         cur->name = xstrdup(name);
         cur->value = xstrdup(value);
-        /*cur->next = 0;*/
         cur->flg_export = flg_export;
         /*cur->flg_read_only = 0;*/
         {
@@ -3242,31 +3263,6 @@ static const char *lookup_param(const char *src)
         return p;
 }
 
-/* Make new string for parser */
-static char* make_string(char **inp)
-{
-        char *p;
-        char *str = NULL;
-        int n;
-        int val_len;
-        int len = 0;
-
-        for (n = 0; inp[n]; n++) {
-                p = expand_variables_to_string(inp[n]);
-                val_len = strlen(p);
-                str = xrealloc(str, len + val_len + 3); /* +3: space, '\n', <nul>*/
-                str[len++] = ' ';
-                strcpy(str + len, p);
-                len += val_len;
-                if (p != inp[n]) free(p);
-        }
-        /* We do not check for case where loop had no iterations at all
-         * - cannot happen? */
-        str[len] = '\n';
-        str[len+1] = '\0';
-        return str;
-}
-
 /* return code: 0 for OK, 1 for syntax error */
 static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
 {
@@ -3358,9 +3354,9 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
         debug_printf_parse("parse_stream entered, end_trigger='%s'\n", end_trigger);
 
         while (1) {
-                ch = b_getch(input);
                 m = CHAR_IFS;
                 next = '\0';
+                ch = b_getch(input);
                 if (ch != EOF) {
                         m = charmap[ch];
                         if (ch != '\n')
@@ -3371,6 +3367,11 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
                 if (m == CHAR_ORDINARY
                  || (m != CHAR_SPECIAL && dest->quote)
                 ) {
+                        if (ch == EOF) {
+                                syntax();
+                                debug_printf_parse("parse_stream return 1: unterminated \"\n");
+                                return 1;
+                        }
                         b_addqchr(dest, ch, dest->quote);
                         continue;
                 }
@@ -3564,8 +3565,8 @@ static void update_charmap(void)
 }
 
 /* most recursion does not come through here, the exception is
- * from builtin_source() */
-static int parse_stream_outer(struct in_str *inp, int parse_flag)
+ * from builtin_source() and builtin_eval() */
+static int parse_and_run_stream(struct in_str *inp, int parse_flag)
 {
         struct p_context ctx;
         o_string temp = NULL_O_STRING;
@@ -3607,19 +3608,19 @@ static int parse_stream_outer(struct in_str *inp, int parse_flag)
         return 0;
 }
 
-static int parse_string_outer(const char *s, int parse_flag)
+static int parse_and_run_string(const char *s, int parse_flag)
 {
         struct in_str input;
         setup_string_in_str(&input, s);
-        return parse_stream_outer(&input, parse_flag);
+        return parse_and_run_stream(&input, parse_flag);
 }
 
-static int parse_file_outer(FILE *f)
+static int parse_and_run_file(FILE *f)
 {
         int rcode;
         struct in_str input;
         setup_file_in_str(&input, f);
-        rcode = parse_stream_outer(&input, PARSEFLAG_SEMICOLON);
+        rcode = parse_and_run_stream(&input, PARSEFLAG_SEMICOLON);
         return rcode;
 }
 
@@ -3698,7 +3699,7 @@ int hush_main(int argc, char **argv)
                 input = fopen("/etc/profile", "r");
                 if (input != NULL) {
                         mark_open(fileno(input));
-                        parse_file_outer(input);
+                        parse_and_run_file(input);
                         mark_closed(fileno(input));
                         fclose(input);
                 }
@@ -3710,7 +3711,7 @@ int hush_main(int argc, char **argv)
                 case 'c':
                         global_argv = argv + optind;
                         global_argc = argc - optind;
-                        opt = parse_string_outer(optarg, PARSEFLAG_SEMICOLON);
+                        opt = parse_and_run_string(optarg, PARSEFLAG_SEMICOLON);
                         goto final_return;
                 case 'i':
                         /* Well, we cannot just declare interactiveness,
@@ -3791,7 +3792,7 @@ int hush_main(int argc, char **argv)
 #endif
 
         if (argv[optind] == NULL) {
-                opt = parse_file_outer(stdin);
+                opt = parse_and_run_file(stdin);
                 goto final_return;
         }
 
@@ -3799,7 +3800,7 @@ int hush_main(int argc, char **argv)
         global_argv = argv + optind;
         global_argc = argc - optind;
         input = xfopen(argv[optind], "r");
-        opt = parse_file_outer(input);
+        opt = parse_and_run_file(input);
 
 #if ENABLE_FEATURE_CLEAN_UP
         fclose(input);
diff --git a/shell/hush_test/hush-bugs/noeol3.right b/shell/hush_test/hush-bugs/noeol3.right
new file mode 100644
index 000000000..a0ce47f30
--- /dev/null
+++ b/shell/hush_test/hush-bugs/noeol3.right
@@ -0,0 +1 @@
+hush: syntax error hush.c:3370
diff --git a/shell/hush_test/hush-bugs/noeol3.tests b/shell/hush_test/hush-bugs/noeol3.tests
new file mode 100755
index 000000000..ec958ed7a
--- /dev/null
+++ b/shell/hush_test/hush-bugs/noeol3.tests
@@ -0,0 +1,2 @@
+# last line has no EOL!
+echo "unterminated
\ No newline at end of file