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#ifdef NO_STRLCPY
 26size_t strlcpy(char *dest, const char *src, size_t size)
 27{
 28	size_t ret = strlen(src);
 
 29
 30	if (size) {
 31		size_t len = (ret >= size) ? size - 1 : ret;
 32		memcpy(dest, src, len);
 33		dest[len] = '\0';
 34	}
 35	return ret;
 36}
 37#endif
 38
 39static char *get_pathname(void)
 40{
 41	static char pathname_array[4][PATH_MAX];
 42	static int idx;
 43
 44	return pathname_array[3 & ++idx];
 45}
 46
 47static char *cleanup_path(char *path)
 48{
 49	/* Clean it up */
 50	if (!memcmp(path, "./", 2)) {
 51		path += 2;
 52		while (*path == '/')
 53			path++;
 54	}
 55	return path;
 56}
 57
 58static char *perf_vsnpath(char *buf, size_t n, const char *fmt, va_list args)
 59{
 60	const char *perf_dir = get_perf_dir();
 61	size_t len;
 62
 63	len = strlen(perf_dir);
 64	if (n < len + 1)
 65		goto bad;
 66	memcpy(buf, perf_dir, len);
 67	if (len && !is_dir_sep(perf_dir[len-1]))
 68		buf[len++] = '/';
 69	len += vsnprintf(buf + len, n - len, fmt, args);
 70	if (len >= n)
 71		goto bad;
 72	return cleanup_path(buf);
 73bad:
 74	strlcpy(buf, bad_path, n);
 75	return buf;
 76}
 77
 78char *perf_pathdup(const char *fmt, ...)
 
 79{
 80	char path[PATH_MAX];
 81	va_list args;
 82	va_start(args, fmt);
 83	(void)perf_vsnpath(path, sizeof(path), fmt, args);
 84	va_end(args);
 85	return xstrdup(path);
 86}
 87
 88char *mkpath(const char *fmt, ...)
 89{
 90	va_list args;
 91	unsigned len;
 92	char *pathname = get_pathname();
 93
 94	va_start(args, fmt);
 95	len = vsnprintf(pathname, PATH_MAX, fmt, args);
 96	va_end(args);
 97	if (len >= PATH_MAX)
 98		return bad_path;
 99	return cleanup_path(pathname);
100}
101
102char *perf_path(const char *fmt, ...)
103{
104	const char *perf_dir = get_perf_dir();
105	char *pathname = get_pathname();
106	va_list args;
107	unsigned len;
108
109	len = strlen(perf_dir);
110	if (len > PATH_MAX-100)
111		return bad_path;
112	memcpy(pathname, perf_dir, len);
113	if (len && perf_dir[len-1] != '/')
114		pathname[len++] = '/';
115	va_start(args, fmt);
116	len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
117	va_end(args);
118	if (len >= PATH_MAX)
119		return bad_path;
120	return cleanup_path(pathname);
121}
122
123/* strip arbitrary amount of directory separators at end of path */
124static inline int chomp_trailing_dir_sep(const char *path, int len)
125{
126	while (len && is_dir_sep(path[len - 1]))
127		len--;
128	return len;
129}
130
131/*
132 * If path ends with suffix (complete path components), returns the
133 * part before suffix (sans trailing directory separators).
134 * Otherwise returns NULL.
135 */
136char *strip_path_suffix(const char *path, const char *suffix)
137{
138	int path_len = strlen(path), suffix_len = strlen(suffix);
139
140	while (suffix_len) {
141		if (!path_len)
142			return NULL;
143
144		if (is_dir_sep(path[path_len - 1])) {
145			if (!is_dir_sep(suffix[suffix_len - 1]))
146				return NULL;
147			path_len = chomp_trailing_dir_sep(path, path_len);
148			suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);
149		}
150		else if (path[--path_len] != suffix[--suffix_len])
151			return NULL;
152	}
153
154	if (path_len && !is_dir_sep(path[path_len - 1]))
155		return NULL;
156	return strndup(path, chomp_trailing_dir_sep(path, path_len));
157}

 1// SPDX-License-Identifier: GPL-2.0
 2#include "path.h"
 
 
 
 
 
 
 
 
 
 
 3#include "cache.h"
 4#include <linux/kernel.h>
 5#include <limits.h>
 6#include <stdio.h>
 7#include <string.h>
 8#include <sys/types.h>
 9#include <sys/stat.h>
10#include <dirent.h>
11#include <unistd.h>
12
13static char *cleanup_path(char *path)
 
 
 
 
 
14{
15	/* Clean it up */
16	if (!memcmp(path, "./", 2)) {
17		path += 2;
18		while (*path == '/')
19			path++;
20	}
21	return path;
22}
23
24char *mkpath(char *path_buf, size_t sz, const char *fmt, ...)
 
25{
26	va_list args;
27	unsigned len;
28
29	va_start(args, fmt);
30	len = vsnprintf(path_buf, sz, fmt, args);
31	va_end(args);
32	if (len >= sz)
33		strncpy(path_buf, "/bad-path/", sz);
34	return cleanup_path(path_buf);
35}
 
36
37int path__join(char *bf, size_t size, const char *path1, const char *path2)
38{
39	return scnprintf(bf, size, "%s%s%s", path1, path1[0] ? "/" : "", path2);
 
 
 
40}
41
42int path__join3(char *bf, size_t size, const char *path1, const char *path2, const char *path3)
43{
44	return scnprintf(bf, size, "%s%s%s%s%s", path1, path1[0] ? "/" : "",
45			 path2, path2[0] ? "/" : "", path3);
 
 
 
 
 
46}
47
48bool is_regular_file(const char *file)
49{
50	struct stat st;
 
51
52	if (stat(file, &st))
53		return false;
54
55	return S_ISREG(st.st_mode);
 
 
 
 
 
 
 
 
 
56}
57
58/* Helper function for filesystems that return a dent->d_type DT_UNKNOWN */
59bool is_directory(const char *base_path, const struct dirent *dent)
60{
61	char path[PATH_MAX];
62	struct stat st;
 
 
 
 
 
63
64	snprintf(path, sizeof(path), "%s/%s", base_path, dent->d_name);
65	if (stat(path, &st))
66		return false;
 
 
67
68	return S_ISDIR(st.st_mode);
 
 
 
 
 
69}
70
71bool is_executable_file(const char *base_path, const struct dirent *dent)
72{
73	char path[PATH_MAX];
74	struct stat st;
 
 
75
76	snprintf(path, sizeof(path), "%s/%s", base_path, dent->d_name);
77	if (stat(path, &st))
78		return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
79
80	return !S_ISDIR(st.st_mode) && (st.st_mode & S_IXUSR);
 
 
81}