2 * I'm tired of doing "vsnprintf()" etc just to open a
3 * file, so here's a "return static buffer with printf"
6 * It's obviously not thread-safe. Sue me. But it's quite
7 * useful for doing things like
9 * f = open(mkpath("%s/%s.perf", base, name), O_RDONLY);
11 * which is what it's designed for.
15 static char bad_path[] = "/bad-path/";
20 static const char *get_perf_dir(void)
26 * If libc has strlcpy() then that version will override this
29 size_t __weak strlcpy(char *dest, const char *src, size_t size)
31 size_t ret = strlen(src);
34 size_t len = (ret >= size) ? size - 1 : ret;
36 memcpy(dest, src, len);
43 static char *get_pathname(void)
45 static char pathname_array[4][PATH_MAX];
48 return pathname_array[3 & ++idx];
51 static char *cleanup_path(char *path)
54 if (!memcmp(path, "./", 2)) {
62 static char *perf_vsnpath(char *buf, size_t n, const char *fmt, va_list args)
64 const char *perf_dir = get_perf_dir();
67 len = strlen(perf_dir);
70 memcpy(buf, perf_dir, len);
71 if (len && !is_dir_sep(perf_dir[len-1]))
73 len += vsnprintf(buf + len, n - len, fmt, args);
76 return cleanup_path(buf);
78 strlcpy(buf, bad_path, n);
82 char *perf_pathdup(const char *fmt, ...)
87 (void)perf_vsnpath(path, sizeof(path), fmt, args);
92 char *mkpath(const char *fmt, ...)
96 char *pathname = get_pathname();
99 len = vsnprintf(pathname, PATH_MAX, fmt, args);
103 return cleanup_path(pathname);
106 char *perf_path(const char *fmt, ...)
108 const char *perf_dir = get_perf_dir();
109 char *pathname = get_pathname();
113 len = strlen(perf_dir);
114 if (len > PATH_MAX-100)
116 memcpy(pathname, perf_dir, len);
117 if (len && perf_dir[len-1] != '/')
118 pathname[len++] = '/';
120 len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
124 return cleanup_path(pathname);
127 /* strip arbitrary amount of directory separators at end of path */
128 static inline int chomp_trailing_dir_sep(const char *path, int len)
130 while (len && is_dir_sep(path[len - 1]))
136 * If path ends with suffix (complete path components), returns the
137 * part before suffix (sans trailing directory separators).
138 * Otherwise returns NULL.
140 char *strip_path_suffix(const char *path, const char *suffix)
142 int path_len = strlen(path), suffix_len = strlen(suffix);
148 if (is_dir_sep(path[path_len - 1])) {
149 if (!is_dir_sep(suffix[suffix_len - 1]))
151 path_len = chomp_trailing_dir_sep(path, path_len);
152 suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
154 else if (path[--path_len] != suffix[--suffix_len])
158 if (path_len && !is_dir_sep(path[path_len - 1]))
160 return strndup(path, chomp_trailing_dir_sep(path, path_len));