1/*
 2 * I'm tired of doing "vsnprintf()" etc just to open a
 3 * file, so here's a "return static buffer with printf"
 4 * interface for paths.
 5 *
 6 * It's obviously not thread-safe. Sue me. But it's quite
 7 * useful for doing things like
 8 *
 9 *   f = open(mkpath("%s/%s.perf", base, name), O_RDONLY);
10 *
11 * which is what it's designed for.
12 */
13#include "cache.h"
14#include "util.h"
15#include <limits.h>
16
17static char bad_path[] = "/bad-path/";
18/*
19 * One hack:
20 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
21static char *get_pathname(void)
22{
23	static char pathname_array[4][PATH_MAX];
24	static int idx;
25
26	return pathname_array[3 & ++idx];
27}
28
29static char *cleanup_path(char *path)
30{
31	/* Clean it up */
32	if (!memcmp(path, "./", 2)) {
33		path += 2;
34		while (*path == '/')
35			path++;
36	}
37	return path;
38}
39
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
40char *mkpath(const char *fmt, ...)
41{
42	va_list args;
43	unsigned len;
44	char *pathname = get_pathname();
45
46	va_start(args, fmt);
47	len = vsnprintf(pathname, PATH_MAX, fmt, args);
48	va_end(args);
49	if (len >= PATH_MAX)
50		return bad_path;
51	return cleanup_path(pathname);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
52}

  1/*
  2 * I'm tired of doing "vsnprintf()" etc just to open a
  3 * file, so here's a "return static buffer with printf"
  4 * interface for paths.
  5 *
  6 * It's obviously not thread-safe. Sue me. But it's quite
  7 * useful for doing things like
  8 *
  9 *   f = open(mkpath("%s/%s.perf", base, name), O_RDONLY);
 10 *
 11 * which is what it's designed for.
 12 */
 13#include "cache.h"
 
 
 14
 15static char bad_path[] = "/bad-path/";
 16/*
 17 * Two hacks:
 18 */
 19
 20static const char *get_perf_dir(void)
 21{
 22	return ".";
 23}
 24
 25/*
 26 * If libc has strlcpy() then that version will override this
 27 * implementation:
 28 */
 29size_t __weak strlcpy(char *dest, const char *src, size_t size)
 30{
 31	size_t ret = strlen(src);
 32
 33	if (size) {
 34		size_t len = (ret >= size) ? size - 1 : ret;
 35
 36		memcpy(dest, src, len);
 37		dest[len] = '\0';
 38	}
 39
 40	return ret;
 41}
 42
 43static char *get_pathname(void)
 44{
 45	static char pathname_array[4][PATH_MAX];
 46	static int idx;
 47
 48	return pathname_array[3 & ++idx];
 49}
 50
 51static char *cleanup_path(char *path)
 52{
 53	/* Clean it up */
 54	if (!memcmp(path, "./", 2)) {
 55		path += 2;
 56		while (*path == '/')
 57			path++;
 58	}
 59	return path;
 60}
 61
 62static char *perf_vsnpath(char *buf, size_t n, const char *fmt, va_list args)
 63{
 64	const char *perf_dir = get_perf_dir();
 65	size_t len;
 66
 67	len = strlen(perf_dir);
 68	if (n < len + 1)
 69		goto bad;
 70	memcpy(buf, perf_dir, len);
 71	if (len && !is_dir_sep(perf_dir[len-1]))
 72		buf[len++] = '/';
 73	len += vsnprintf(buf + len, n - len, fmt, args);
 74	if (len >= n)
 75		goto bad;
 76	return cleanup_path(buf);
 77bad:
 78	strlcpy(buf, bad_path, n);
 79	return buf;
 80}
 81
 82char *perf_pathdup(const char *fmt, ...)
 83{
 84	char path[PATH_MAX];
 85	va_list args;
 86	va_start(args, fmt);
 87	(void)perf_vsnpath(path, sizeof(path), fmt, args);
 88	va_end(args);
 89	return xstrdup(path);
 90}
 91
 92char *mkpath(const char *fmt, ...)
 93{
 94	va_list args;
 95	unsigned len;
 96	char *pathname = get_pathname();
 97
 98	va_start(args, fmt);
 99	len = vsnprintf(pathname, PATH_MAX, fmt, args);
100	va_end(args);
101	if (len >= PATH_MAX)
102		return bad_path;
103	return cleanup_path(pathname);
104}
105
106char *perf_path(const char *fmt, ...)
107{
108	const char *perf_dir = get_perf_dir();
109	char *pathname = get_pathname();
110	va_list args;
111	unsigned len;
112
113	len = strlen(perf_dir);
114	if (len > PATH_MAX-100)
115		return bad_path;
116	memcpy(pathname, perf_dir, len);
117	if (len && perf_dir[len-1] != '/')
118		pathname[len++] = '/';
119	va_start(args, fmt);
120	len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
121	va_end(args);
122	if (len >= PATH_MAX)
123		return bad_path;
124	return cleanup_path(pathname);
125}
126
127/* strip arbitrary amount of directory separators at end of path */
128static inline int chomp_trailing_dir_sep(const char *path, int len)
129{
130	while (len && is_dir_sep(path[len - 1]))
131		len--;
132	return len;
133}
134
135/*
136 * If path ends with suffix (complete path components), returns the
137 * part before suffix (sans trailing directory separators).
138 * Otherwise returns NULL.
139 */
140char *strip_path_suffix(const char *path, const char *suffix)
141{
142	int path_len = strlen(path), suffix_len = strlen(suffix);
143
144	while (suffix_len) {
145		if (!path_len)
146			return NULL;
147
148		if (is_dir_sep(path[path_len - 1])) {
149			if (!is_dir_sep(suffix[suffix_len - 1]))
150				return NULL;
151			path_len = chomp_trailing_dir_sep(path, path_len);
152			suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
153		}
154		else if (path[--path_len] != suffix[--suffix_len])
155			return NULL;
156	}
157
158	if (path_len && !is_dir_sep(path[path_len - 1]))
159		return NULL;
160	return strndup(path, chomp_trailing_dir_sep(path, path_len));
161}