[PATCH v5 13/14] perf: Re-Add make_absolute_path

Srikar Dronamraju
2010-06-14T08:32:22Z

revert_make_absolute_path.patch

From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>

perf probe for uprobes would use make_absolute_path.
make_absolute_path can be used to convert a file name to a dso name.

so if user specifies the function to be traced as malloc@/lib/libc.so.6
it needs to be converted to malloc@libc-2.5.so

This patch reverts a part of a41794cdd7ee94a5199e14f642c26d649d383fa5
---

tools/perf/util/abspath.c | 81 +++++++++++++++++++++++++++++++++++++++++++++
tools/perf/util/cache.h | 1 +
2 files changed, 82 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/abspath.c b/tools/perf/util/abspath.c
index 0e76aff..a791dd4 100644
--- a/tools/perf/util/abspath.c
+++ b/tools/perf/util/abspath.c
@@ -1,5 +1,86 @@
#include "cache.h"

+/*
+ * Do not use this for inspecting *tracked* content. When path is a
+ * symlink to a directory, we do not want to say it is a directory when
+ * dealing with tracked content in the working tree.
+ */
+static int is_directory(const char *path)
+{
+ struct stat st;
+ return (!stat(path, &st) && S_ISDIR(st.st_mode));
+}
+
+/* We allow "recursive" symbolic links. Only within reason, though. */
+#define MAXDEPTH 5
+
+const char *make_absolute_path(const char *path)
+{
+ static char bufs[2][PATH_MAX + 1], *buf = bufs[0], *next_buf = bufs[1];
+ char cwd[1024] = "";
+ int buf_index = 1, len;
+
+ int depth = MAXDEPTH;
+ char *last_elem = NULL;
+ struct stat st;
+
+ if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
+ die ("Too long path: %.*s", 60, path);
+
+ while (depth--) {
+ if (!is_directory(buf)) {
+ char *last_slash = strrchr(buf, '/');
+ if (last_slash) {
+ *last_slash = '\0';
+ last_elem = xstrdup(last_slash + 1);
+ } else {
+ last_elem = xstrdup(buf);
+ *buf = '\0';
+ }
+ }
+
+ if (*buf) {
+ if (!*cwd && !getcwd(cwd, sizeof(cwd)))
+ die ("Could not get current working directory");
+
+ if (chdir(buf))
+ die ("Could not switch to '%s'", buf);
+ }
+ if (!getcwd(buf, PATH_MAX))
+ die ("Could not get current working directory");
+
+ if (last_elem) {
+ len = strlen(buf);
+
+ if (len + strlen(last_elem) + 2 > PATH_MAX)
+ die ("Too long path name: '%s/%s'",
+ buf, last_elem);
+ buf[len] = '/';
+ strcpy(buf + len + 1, last_elem);
+ free(last_elem);
+ last_elem = NULL;
+ }
+
+ if (!lstat(buf, &st) && S_ISLNK(st.st_mode)) {
+ len = readlink(buf, next_buf, PATH_MAX);
+ if (len < 0)
+ die ("Invalid symlink: %s", buf);
+ if (PATH_MAX <= len)
+ die("symbolic link too long: %s", buf);
+ next_buf[len] = '\0';
+ buf = next_buf;
+ buf_index = 1 - buf_index;
+ next_buf = bufs[buf_index];
+ } else
+ break;
+ }
+
+ if (*cwd && chdir(cwd))
+ die ("Could not change back to '%s'", cwd);
+
+ return buf;
+}
+
static const char *get_pwd_cwd(void)
{
static char cwd[PATH_MAX + 1];
diff --git a/tools/perf/util/cache.h b/tools/perf/util/cache.h
index 27e9ebe..0dfed40 100644
--- a/tools/perf/util/cache.h
+++ b/tools/perf/util/cache.h
@@ -73,6 +73,7 @@ static inline int is_absolute_path(const char *path)
return path[0] == '/';
}

+const char *make_absolute_path(const char *path);
const char *make_nonrelative_path(const char *path);
char *strip_path_suffix(const char *path, const char *suffix);