[Libguestfs] [PATCH 1/2] filearch: move libmagic code in an own function
Also use a cleanup attribue to ease the close of the magic_t handle.
This is mostly code motion, hopefully with no actual behaviour changes.
---
src/filearch.c | 100 +++++++++++++++++++++++++++++++++++++++------------------
1 file changed, 68 insertions(+), 32 deletions(-)
diff --git a/src/filearch.c b/src/filearch.c
index 8708a4b..219eaae 100644
--- a/src/filearch.c
+++ b/src/filearch.c
@@ -42,6 +42,22 @@
#if defined(HAVE_LIBMAGIC)
+# ifdef HAVE_ATTRIBUTE_CLEANUP
+# define CLEANUP_MAGIC_T_FREE __attribute__((cleanup(cleanup_magic_t_free)))
+
+static void
+cleanup_magic_t_free (void *ptr)
+{
+ magic_t m = *(magic_t *) ptr;
+
+ if (m)
+ magic_close (m);
+}
+
+# else
+# define CLEANUP_MAGIC_T_FREE
+# endif
+
COMPILE_REGEXP (re_file_elf,
"ELF.*(?:executable|shared object|relocatable), (.+?),", 0)
COMPILE_REGEXP (re_elf_ppc64, "64.*PowerPC", 0)
@@ -92,6 +108,55 @@ is_regular_file (const char *filename)
return lstat (filename, &statbuf) == 0 && S_ISREG (statbuf.st_mode);
}
+static char *
+magic_for_file (guestfs_h *g, const char *filename, bool *loading_ok,
+ bool *matched)
+{
+ int flags;
+ CLEANUP_MAGIC_T_FREE magic_t m = NULL;
+ const char *line;
+ char *elf_arch;
+
+ flags = g->verbose ? MAGIC_DEBUG : 0;
+ flags |= MAGIC_ERROR | MAGIC_RAW;
+
+ if (loading_ok)
+ *loading_ok = false;
+ if (matched)
+ *matched = false;
+
+ m = magic_open (flags);
+ if (m == NULL) {
+ perrorf (g, "magic_open");
+ return NULL;
+ }
+
+ if (magic_load (m, NULL) == -1) {
+ perrorf (g, "magic_load: default magic database file");
+ return NULL;
+ }
+
+ line = magic_file (m, filename);
+ if (line == NULL) {
+ perrorf (g, "magic_file: %s", filename);
+ return NULL;
+ }
+
+ if (loading_ok)
+ *loading_ok = true;
+
+ elf_arch = match1 (g, line, re_file_elf);
+ if (elf_arch == NULL) {
+ error (g, "no re_file_elf match in '%s'", line);
+ return NULL;
+ }
+
+ if (matched)
+ *matched = true;
+
+ return canonical_elf_arch (g, elf_arch);
+}
+
/* Download and uncompress the cpio file to find binaries within. */
static const char *initrd_binaries[] = {
"bin/ls",
@@ -170,40 +235,11 @@ cpio_arch (guestfs_h *g, const char *file, const char *path)
safe_asprintf (g, "%s/%s", dir, initrd_binaries[i]);
if (is_regular_file (bin)) {
- int flags;
- magic_t m;
- const char *line;
- CLEANUP_FREE char *elf_arch = NULL;
-
- flags = g->verbose ? MAGIC_DEBUG : 0;
- flags |= MAGIC_ERROR | MAGIC_RAW;
-
- m = magic_open (flags);
- if (m == NULL) {
- perrorf (g, "magic_open");
- goto out;
- }
-
- if (magic_load (m, NULL) == -1) {
- perrorf (g, "magic_load: default magic database file");
- magic_close (m);
- goto out;
- }
-
- line = magic_file (m, bin);
- if (line == NULL) {
- perrorf (g, "magic_file: %s", bin);
- magic_close (m);
- goto out;
- }
+ bool loading_ok, matched;
- elf_arch = match1 (g, line, re_file_elf);
- if (elf_arch != NULL) {
- ret = canonical_elf_arch (g, elf_arch);
- magic_close (m);
+ ret = magic_for_file (g, bin, &loading_ok, &matched);
+ if (!loading_ok || matched)
goto out;
- }
- magic_close (m);
}
}
error (g, "file_architecture: could not determine architecture of cpio
archive");
--
2.1.0