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/*
* 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 ".";
}
size_t 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;
}
char *mksnpath(char *buf, size_t n, const char *fmt, ...)
{
va_list args;
unsigned len;
va_start(args, fmt);
len = vsnprintf(buf, n, fmt, args);
va_end(args);
if (len >= n) {
strlcpy(buf, bad_path, n);
return buf;
}
return cleanup_path(buf);
}
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_snpath(char *buf, size_t n, const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
(void)perf_vsnpath(buf, n, fmt, args);
va_end(args);
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);
}
/* perf_mkstemp() - create tmp file honoring TMPDIR variable */
int perf_mkstemp(char *path, size_t len, const char *template)
{
const char *tmp;
size_t n;
tmp = getenv("TMPDIR");
if (!tmp)
tmp = "/tmp";
n = snprintf(path, len, "%s/%s", tmp, template);
if (len <= n) {
errno = ENAMETOOLONG;
return -1;
}
return mkstemp(path);
}
const char *make_relative_path(const char *abs_path, const char *base)
{
static char buf[PATH_MAX + 1];
int baselen;
if (!base)
return abs_path;
baselen = strlen(base);
if (prefixcmp(abs_path, base))
return abs_path;
if (abs_path[baselen] == '/')
baselen++;
else if (base[baselen - 1] != '/')
return abs_path;
strcpy(buf, abs_path + baselen);
return buf;
}
/*
* It is okay if dst == src, but they should not overlap otherwise.
*
* Performs the following normalizations on src, storing the result in dst:
* - Ensures that components are separated by '/' (Windows only)
* - Squashes sequences of '/'.
* - Removes "." components.
* - Removes ".." components, and the components the precede them.
* Returns failure (non-zero) if a ".." component appears as first path
* component anytime during the normalization. Otherwise, returns success (0).
*
* Note that this function is purely textual. It does not follow symlinks,
* verify the existence of the path, or make any system calls.
*/
int normalize_path_copy(char *dst, const char *src)
{
char *dst0;
if (has_dos_drive_prefix(src)) {
*dst++ = *src++;
*dst++ = *src++;
}
dst0 = dst;
if (is_dir_sep(*src)) {
*dst++ = '/';
while (is_dir_sep(*src))
src++;
}
for (;;) {
char c = *src;
/*
* A path component that begins with . could be
* special:
* (1) "." and ends -- ignore and terminate.
* (2) "./" -- ignore them, eat slash and continue.
* (3) ".." and ends -- strip one and terminate.
* (4) "../" -- strip one, eat slash and continue.
*/
if (c == '.') {
if (!src[1]) {
/* (1) */
src++;
} else if (is_dir_sep(src[1])) {
/* (2) */
src += 2;
while (is_dir_sep(*src))
src++;
continue;
} else if (src[1] == '.') {
if (!src[2]) {
/* (3) */
src += 2;
goto up_one;
} else if (is_dir_sep(src[2])) {
/* (4) */
src += 3;
while (is_dir_sep(*src))
src++;
goto up_one;
}
}
}
/* copy up to the next '/', and eat all '/' */
while ((c = *src++) != '\0' && !is_dir_sep(c))
*dst++ = c;
if (is_dir_sep(c)) {
*dst++ = '/';
while (is_dir_sep(c))
c = *src++;
src--;
} else if (!c)
break;
continue;
up_one:
/*
* dst0..dst is prefix portion, and dst[-1] is '/';
* go up one level.
*/
dst--; /* go to trailing '/' */
if (dst <= dst0)
return -1;
/* Windows: dst[-1] cannot be backslash anymore */
while (dst0 < dst && dst[-1] != '/')
dst--;
}
*dst = '\0';
return 0;
}
/*
* path = Canonical absolute path
* prefix_list = Colon-separated list of absolute paths
*
* Determines, for each path in prefix_list, whether the "prefix" really
* is an ancestor directory of path. Returns the length of the longest
* ancestor directory, excluding any trailing slashes, or -1 if no prefix
* is an ancestor. (Note that this means 0 is returned if prefix_list is
* "/".) "/fo
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