Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / tools / perf / util / path.c

diff --git a/kernel/tools/perf/util/path.c b/kernel/tools/perf/util/path.c
new file mode 100644 (file)
index 0000000..5d13cb4
--- /dev/null
+++ b/kernel/tools/perf/util/path.c
@@ -0,0 +1,161 @@
+/*
+ * I'm tired of doing "vsnprintf()" etc just to open a
+ * file, so here's a "return static buffer with printf"
+ * interface for paths.
+ *
+ * It's obviously not thread-safe. Sue me. But it's quite
+ * useful for doing things like
+ *
+ *   f = open(mkpath("%s/%s.perf", base, name), O_RDONLY);
+ *
+ * which is what it's designed for.
+ */
+#include "cache.h"
+
+static char bad_path[] = "/bad-path/";
+/*
+ * Two hacks:
+ */
+
+static const char *get_perf_dir(void)
+{
+       return ".";
+}
+
+/*
+ * If libc has strlcpy() then that version will override this
+ * implementation:
+ */
+size_t __weak strlcpy(char *dest, const char *src, size_t size)
+{
+       size_t ret = strlen(src);
+
+       if (size) {
+               size_t len = (ret >= size) ? size - 1 : ret;
+
+               memcpy(dest, src, len);
+               dest[len] = '\0';
+       }
+
+       return ret;
+}
+
+static char *get_pathname(void)
+{
+       static char pathname_array[4][PATH_MAX];
+       static int idx;
+
+       return pathname_array[3 & ++idx];
+}
+
+static char *cleanup_path(char *path)
+{
+       /* Clean it up */
+       if (!memcmp(path, "./", 2)) {
+               path += 2;
+               while (*path == '/')
+                       path++;
+       }
+       return path;
+}
+
+static char *perf_vsnpath(char *buf, size_t n, const char *fmt, va_list args)
+{
+       const char *perf_dir = get_perf_dir();
+       size_t len;
+
+       len = strlen(perf_dir);
+       if (n < len + 1)
+               goto bad;
+       memcpy(buf, perf_dir, len);
+       if (len && !is_dir_sep(perf_dir[len-1]))
+               buf[len++] = '/';
+       len += vsnprintf(buf + len, n - len, fmt, args);
+       if (len >= n)
+               goto bad;
+       return cleanup_path(buf);
+bad:
+       strlcpy(buf, bad_path, n);
+       return buf;
+}
+
+char *perf_pathdup(const char *fmt, ...)
+{
+       char path[PATH_MAX];
+       va_list args;
+       va_start(args, fmt);
+       (void)perf_vsnpath(path, sizeof(path), fmt, args);
+       va_end(args);
+       return xstrdup(path);
+}
+
+char *mkpath(const char *fmt, ...)
+{
+       va_list args;
+       unsigned len;
+       char *pathname = get_pathname();
+
+       va_start(args, fmt);
+       len = vsnprintf(pathname, PATH_MAX, fmt, args);
+       va_end(args);
+       if (len >= PATH_MAX)
+               return bad_path;
+       return cleanup_path(pathname);
+}
+
+char *perf_path(const char *fmt, ...)
+{
+       const char *perf_dir = get_perf_dir();
+       char *pathname = get_pathname();
+       va_list args;
+       unsigned len;
+
+       len = strlen(perf_dir);
+       if (len > PATH_MAX-100)
+               return bad_path;
+       memcpy(pathname, perf_dir, len);
+       if (len && perf_dir[len-1] != '/')
+               pathname[len++] = '/';
+       va_start(args, fmt);
+       len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
+       va_end(args);
+       if (len >= PATH_MAX)
+               return bad_path;
+       return cleanup_path(pathname);
+}
+
+/* strip arbitrary amount of directory separators at end of path */
+static inline int chomp_trailing_dir_sep(const char *path, int len)
+{
+       while (len && is_dir_sep(path[len - 1]))
+               len--;
+       return len;
+}
+
+/*
+ * If path ends with suffix (complete path components), returns the
+ * part before suffix (sans trailing directory separators).
+ * Otherwise returns NULL.
+ */
+char *strip_path_suffix(const char *path, const char *suffix)
+{
+       int path_len = strlen(path), suffix_len = strlen(suffix);
+
+       while (suffix_len) {
+               if (!path_len)
+                       return NULL;
+
+               if (is_dir_sep(path[path_len - 1])) {
+                       if (!is_dir_sep(suffix[suffix_len - 1]))
+                               return NULL;
+                       path_len = chomp_trailing_dir_sep(path, path_len);
+                       suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
+               }
+               else if (path[--path_len] != suffix[--suffix_len])
+                       return NULL;
+       }
+
+       if (path_len && !is_dir_sep(path[path_len - 1]))
+               return NULL;
+       return strndup(path, chomp_trailing_dir_sep(path, path_len));
+}