Replace utils/mount.fuse "sh" script with a "C" program

1 files changed, 151 insertions, 0 deletions

diff --git a/util/mount.fuse.c b/util/mount.fuse.c
new file mode 100644
index 0000000..d156009
--- /dev/null
+++ b/util/mount.fuse.c
@@ -0,0 +1,151 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+static char *progname;
+
+
+static char *xstrdup(const char *s)
+{
+    char *t = strdup(s);
+    if (!t) {
+        fprintf(stderr, "%s: failed to allocate memory\n", progname);
+        exit(1);
+    }
+    return t;
+}
+
+static void *xrealloc(void *oldptr, size_t size)
+{
+    void *ptr = realloc(oldptr, size);
+    if (!ptr) {
+        fprintf(stderr, "%s: failed to allocate memory\n", progname);
+        exit(1);
+    }
+    return ptr;
+}
+
+static void add_arg(char **cmdp, const char *opt)
+{
+    size_t optlen = strlen(opt);
+    size_t cmdlen = *cmdp ? strlen(*cmdp) : 0;
+    char *cmd = xrealloc(*cmdp, cmdlen + optlen * 4 + 4);
+    char *s;
+    s = cmd + cmdlen;
+    if (*cmdp)
+        *s++ = ' ';
+
+    *s++ = '\'';
+    for (; *opt; opt++) {
+        if (*opt == '\'') {
+            *s++ = '\'';
+            *s++ = '\\';
+            *s++ = '\'';
+            *s++ = '\'';
+        } else
+            *s++ = *opt;
+    }
+    *s++ = '\'';
+    *s = '\0';
+    *cmdp = cmd;
+}
+
+int main(int argc, char *argv[])
+{
+    char *type;
+    char *source;
+    const char *mountpoint;
+    char *options = NULL;
+    char *command = NULL;
+    char *setuid = NULL;
+    int i;
+
+    progname = argv[0];
+    if (argc < 3) {
+        fprintf(stderr,
+                "usage: %s type#[source] mountpoint [-o opt[,opts...]]\n",
+                progname);
+        exit(1);
+    }
+
+    type = xstrdup(argv[1]);
+    source = strchr(type, '#');
+    if (source)
+        *source++ = '\0';
+
+    if (!type[0]) {
+        fprintf(stderr, "%s: empty filesystem type\n", progname);
+        exit(1);
+    }
+    mountpoint = argv[2];
+
+    for (i = 3; i < argc; i++) {
+        if (strcmp(argv[i], "-v") == 0)
+            continue;
+        if (strcmp(argv[i], "-o") == 0) {
+            char *opts;
+            char *opt;
+            i++;
+            if (i == argc)
+                break;
+
+            opts = xstrdup(argv[i]);
+            opt = strtok(opts, ",");
+            while (opt) {
+                int j;
+                int ignore = 0;
+                const char *ignore_opts[] = { "", "user", "nouser", "users",
+                                              "auto", "noauto", "_netdev",
+                                              NULL};
+                if (strncmp(opt, "setuid=", 7) == 0) {
+                    setuid = xstrdup(opt + 7);
+                    ignore = 1;
+                }
+                for (j = 0; ignore_opts[j]; j++)
+                    if (strcmp(opt, ignore_opts[j]) == 0)
+                        ignore = 1;
+
+                if (!ignore) {
+                    int oldlen = options ? strlen(options) : 0;
+                    options = xrealloc(options, oldlen + 1 + strlen(opt) + 1);
+                    if (!oldlen)
+                        strcpy(options, opt);
+                    else {
+                        strcat(options, ",");
+                        strcat(options, opt);
+                    }
+                }
+                opt = strtok(NULL, ",");
+            }
+        }
+    }
+
+    add_arg(&command, type);
+    if (source)
+        add_arg(&command, source);
+    add_arg(&command, mountpoint);
+    if (options) {
+        add_arg(&command, "-o");
+        add_arg(&command, options);
+    }
+
+    if (setuid && setuid[0]) {
+        char *sucommand = command;
+        command = NULL;
+        add_arg(&command, "su");
+        add_arg(&command, "-");
+        add_arg(&command, setuid);
+        add_arg(&command, "-c");
+        add_arg(&command, sucommand);
+    } else if (!getenv("HOME")) {
+        /* Hack to make filesystems work in the boot environment */
+        setenv("HOME", "/root", 0);
+    }
+
+    execl("/bin/sh", "/bin/sh", "-c", command, NULL);
+    fprintf(stderr, "%s: failed to execute /bin/sh: %s\n", progname,
+            strerror(errno));
+    return 1;
+}