Show the source dir in the first field on /etc/mtab.

Fixes #15. Thanks @tyll!

4 files changed, 55 insertions, 1 deletions

diff --git a/src/bindfs.c b/src/bindfs.c
index 0aa0a51..a40d578 100644
--- a/src/bindfs.c
+++ b/src/bindfs.c
@@ -1993,6 +1993,13 @@ int main(int argc, char *argv[])
     fuse_opt_add_arg(&args, "-ouse_ino");
     fuse_opt_add_arg(&args, "-oreaddir_ino");
 
+    /* Show the source dir in the first field on /etc/mtab. */
+    {
+        char *tmp = sprintf_new("-ofsname=%s", settings.mntsrc);
+        fuse_opt_add_arg(&args, tmp);
+        free(tmp);
+    }
+
     /* We need to disable the attribute cache whenever two users
        can see different attributes. For now, only mirroring can do that. */
     if (is_mirroring_enabled()) {
diff --git a/src/misc.c b/src/misc.c
index 612ec82..e0aba02 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -18,6 +18,8 @@
 */
 
 #include "misc.h"
+#include <stdarg.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
@@ -68,6 +70,31 @@ char *strdup_until(const char *s, const char *endchars)
     }
 }
 
+char *sprintf_new(const char *format, ...)
+{
+    va_list ap;
+    size_t buffer_size = strlen(format) + 32;
+    char *buffer = malloc(buffer_size);
+    if (buffer == NULL) {
+        return NULL;
+    }
+
+    while (1) {
+        va_start(ap, format);
+        size_t len = (size_t)vsnprintf(buffer, buffer_size, format, ap);
+        va_end(ap);
+        if (len < buffer_size) {
+            return buffer;
+        }
+        free(buffer);
+        buffer_size *= 2;
+        buffer = malloc(buffer_size);
+        if (buffer == NULL) {
+            return NULL;
+        }
+    }
+}
+
 const char *my_basename(const char *path)
 {
     const char *p;
diff --git a/src/misc.h b/src/misc.h
index dc654d6..b059596 100644
--- a/src/misc.h
+++ b/src/misc.h
@@ -31,6 +31,9 @@ int count_substrs(const char *s, const char *sub);
    an end character is reached. */
 char *strdup_until(const char *s, const char *endchars);
 
+/* Like sprintf but writes to an automatically malloc'ed buffer. */
+char *sprintf_new(const char *format, ...);
+
 /* Returns a pointer to the first character after the
    final slash of path, or path itself if it contains no slashes.
    If the path ends with a slash, then the result is an empty
diff --git a/tests/internals/test_internals.c b/tests/internals/test_internals.c
index aba4045..f5dbed5 100644
--- a/tests/internals/test_internals.c
+++ b/tests/internals/test_internals.c
@@ -52,4 +52,21 @@ void my_dirname_suite()
     test_my_dirname(buf, "..");
 }
 
-TEST_MAIN(my_dirname_suite);
+void sprintf_new_suite() {
+    char *result;
+
+    result = sprintf_new("Hello %d %s", 123, "World");
+    TEST_ASSERT(strcmp(result, "Hello 123 World") == 0);
+    free(result);
+
+    result = sprintf_new("A %s", "loooooooooooooooooooooooooong result");
+    TEST_ASSERT(strcmp(result, "A loooooooooooooooooooooooooong result") == 0);
+    free(result);
+}
+
+void test_internal_suite() {
+    my_dirname_suite();
+    sprintf_new_suite();
+}
+
+TEST_MAIN(test_internal_suite);