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#include "cache.h"
struct pathname {
int len;
char path[PATH_MAX];
};
/* Return matching pathname prefix length, or zero if not matching */
static inline int match_pathname(int len, const char *name, struct pathname *match)
{
int match_len = match->len;
return (len > match_len &&
name[match_len] == '/' &&
!memcmp(name, match->path, match_len)) ? match_len : 0;
}
static inline void set_pathname(int len, const char *name, struct pathname *match)
{
if (len < PATH_MAX) {
match->len = len;
memcpy(match->path, name, len);
match->path[len] = 0;
}
}
int has_symlink_leading_path(int len, const char *name)
{
static struct pathname link, nonlink;
char path[PATH_MAX];
struct stat st;
char *sp;
int known_dir;
/*
* See if the last known symlink cache matches.
*/
if (match_pathname(len, name, &link))
return 1;
/*
* Get rid of the last known directory part
*/
known_dir = match_pathname(len, name, &nonlink);
while ((sp = strchr(name + known_dir + 1, '/')) != NULL) {
int thislen = sp - name ;
memcpy(path, name, thislen);
path[thislen] = 0;
if (lstat(path, &st))
return 0;
if (S_ISDIR(st.st_mode)) {
set_pathname(thislen, path, &nonlink);
known_dir = thislen;
continue;
}
if (S_ISLNK(st.st_mode)) {
set_pathname(thislen, path, &link);
return 1;
}
break;
}
return 0;
}
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