fsck: more clever (->smaller) handling of parameters

function                                             old     new   delta
fsck_device                                          213     449    +236
new_args                                               -      46     +46
fsck_main                                           1870    1815     -55
execute                                              289       -    -289
------------------------------------------------------------------------------
(add/remove: 1/1 grow/shrink: 1/1 up/down: 282/-344)          Total: -62 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/e2fsprogs/fsck.c b/e2fsprogs/fsck.c
index c4d0b03ef66289c818755f75bbc31d5cde7e2166..21b2fdc0d861f562d632e7d9851095d1f9408721 100644 (file)
--- a/e2fsprogs/fsck.c
+++ b/e2fsprogs/fsck.c
@@ -490,60 +490,55 @@ static int wait_many(int flags)
 static void execute(const char *type, const char *device,
                const char *mntpt /*, int interactive */)
 {
-       char *argv[num_args + 4]; /* see count below: */
-       int argc;
        int i;
        struct fsck_instance *inst;
        pid_t pid;
 
-       argv[0] = xasprintf("fsck.%s", type); /* 1 */
-       for (i = 0; i < num_args; i++)
-               argv[i+1] = args[i]; /* num_args */
-       argc = num_args + 1;
+       args[0] = xasprintf("fsck.%s", type);
 
 #if DO_PROGRESS_INDICATOR
        if (progress && !progress_active()) {
                if (strcmp(type, "ext2") == 0
                 || strcmp(type, "ext3") == 0
                ) {
-                       argv[argc++] = xasprintf("-C%d", progress_fd); /* 1 */
+                       args[XXX] = xasprintf("-C%d", progress_fd); /* 1 */
                        inst->flags |= FLAG_PROGRESS;
                }
        }
 #endif
 
-       argv[argc++] = (char*)device; /* 1 */
-       argv[argc] = NULL; /* 1 */
+       args[num_args - 2] = (char*)device;
+       /* args[num_args - 1] = NULL; - already is */
 
        if (verbose || noexecute) {
-               printf("[%s (%d) -- %s]", argv[0], num_running,
+               printf("[%s (%d) -- %s]", args[0], num_running,
                                        mntpt ? mntpt : device);
-               for (i = 0; i < argc; i++)
-                       printf(" %s", argv[i]);
+               for (i = 0; args[i]; i++)
+                       printf(" %s", args[i]);
                bb_putchar('\n');
        }
 
        /* Fork and execute the correct program. */
        pid = -1;
        if (!noexecute) {
-               pid = spawn(argv);
+               pid = spawn(args);
                if (pid < 0)
-                       bb_simple_perror_msg(argv[0]);
+                       bb_simple_perror_msg(args[0]);
        }
 
 #if DO_PROGRESS_INDICATOR
-       free(argv[num_args + 1]);
+       free(args[XXX]);
 #endif
 
        /* No child, so don't record an instance */
        if (pid <= 0) {
-               free(argv[0]);
+               free(args[0]);
                return;
        }
 
        inst = xzalloc(sizeof(*inst));
        inst->pid = pid;
-       inst->prog = argv[0];
+       inst->prog = args[0];
        inst->device = xstrdup(device);
        inst->base_device = base_device(device);
 #if DO_PROGRESS_INDICATOR
@@ -899,6 +894,12 @@ static void compile_fs_type(char *fs_type)
        }
 }
 
+static char **new_args(void)
+{
+       args = xrealloc_vector(args, 2, num_args);
+       return &args[num_args++];
+}
+
 int fsck_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int fsck_main(int argc UNUSED_PARAM, char **argv)
 {
@@ -922,11 +923,9 @@ int fsck_main(int argc UNUSED_PARAM, char **argv)
        opts_for_fsck = doall = notitle = 0;
        devices = NULL;
        num_devices = 0;
-       /* in bss, so already zeroed
-       args = NULL;
-       num_args = 0;
-       instance_list = NULL;
-       */
+       new_args(); /* args[0] = NULL, will be replaced by fsck.<type> */
+       /* instance_list = NULL; - in bss, so already zeroed */
+
        while (*++argv) {
                int j;
                int optpos;
@@ -944,8 +943,7 @@ int fsck_main(int argc UNUSED_PARAM, char **argv)
                }
 
                if (arg[0] != '-' || opts_for_fsck) {
-                       args = xrealloc_vector(args, 2, num_args);
-                       args[num_args++] = arg;
+                       *new_args() = arg;
                        continue;
                }
 
@@ -1022,8 +1020,7 @@ int fsck_main(int argc UNUSED_PARAM, char **argv)
                if (optpos) {
                        options[0] = '-';
                        options[optpos + 1] = '\0';
-                       args = xrealloc_vector(args, 2, num_args);
-                       args[num_args++] = options;
+                       *new_args() = options;
                }
        }
        if (getenv("FSCK_FORCE_ALL_PARALLEL"))
@@ -1031,6 +1028,8 @@ int fsck_main(int argc UNUSED_PARAM, char **argv)
        tmp = getenv("FSCK_MAX_INST");
        if (tmp)
                max_running = xatoi(tmp);
+       new_args(); /* args[num_args - 2] will be replaced by <device> */
+       new_args(); /* args[num_args - 1] is the last, NULL element */
 
        if (!notitle)
                puts("fsck (busybox "BB_VER", "BB_BT")");