[PATCH 06/26] perf tools: Add support to read build id from compressed elf

[Jiri Olsa]

Adding support to decompress file before reading build id.

Adding filename__read_build_id and change its current
versions to read_build_id.

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
 tools/perf/util/symbol-elf.c | 37 ++++++++++++++++++++++++++++++++++--
 1 file changed, 35 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 94a156df22d5..6770572620f3 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -534,7 +534,7 @@ static int elf_read_build_id(Elf *elf, void *bf, size_t size)
 
 #ifdef HAVE_LIBBFD_BUILDID_SUPPORT
 
-int filename__read_build_id(const char *filename, void *bf, size_t size)
+static int read_build_id(const char *filename, void *bf, size_t size)
 {
 	int err = -1;
 	bfd *abfd;
@@ -562,7 +562,7 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
 
 #else // HAVE_LIBBFD_BUILDID_SUPPORT
 
-int filename__read_build_id(const char *filename, void *bf, size_t size)
+static int read_build_id(const char *filename, void *bf, size_t size)
 {
 	int fd, err = -1;
 	Elf *elf;
@@ -591,6 +591,39 @@ int filename__read_build_id(const char *filename, void *bf, size_t size)
 
 #endif // HAVE_LIBBFD_BUILDID_SUPPORT
 
+int filename__read_build_id(const char *filename, void *bf, size_t size)
+{
+	struct kmod_path m = { .name = NULL, };
+	char path[PATH_MAX];
+	int err;
+
+	if (!filename)
+		return -EFAULT;
+
+	err = kmod_path__parse(&m, filename);
+	if (err)
+		return -1;
+
+	if (m.comp) {
+		int error = 0, fd;
+
+		fd = filename__decompress(filename, path, sizeof(path), m.comp, &error);
+		if (fd < 0) {
+			pr_debug("Failed to decompress (error %d) %s\n",
+				 error, filename);
+			return -1;
+		}
+		close(fd);
+		filename = path;
+	}
+
+	err = read_build_id(filename, bf, size);
+
+	if (m.comp)
+		unlink(filename);
+	return err;
+}
+
 int sysfs__read_build_id(const char *filename, void *build_id, size_t size)
 {
 	int fd, err = -1;
-- 
2.26.2