/* * 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 ".";} /* * If libc has strlcpy() then that version will override this * implementation: */size_t __weak 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;} 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_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);} /* strip arbitrary amount of directory separators at end of path */static inline int chomp_trailing_dir_sep(const char *path, int len){	while (len && is_dir_sep(path[len - 1]))		len--;	return len;} /* * If path ends with suffix (complete path components), returns the * part before suffix (sans trailing directory separators). * Otherwise returns NULL. */char *strip_path_suffix(const char *path, const char *suffix){	int path_len = strlen(path), suffix_len = strlen(suffix); 	while (suffix_len) {		if (!path_len)			return NULL; 		if (is_dir_sep(path[path_len - 1])) {			if (!is_dir_sep(suffix[suffix_len - 1]))				return NULL;			path_len = chomp_trailing_dir_sep(path, path_len);			suffix_len = chomp_trailing_dir_sep(suffix, suffix_len);		}		else if (path[--path_len] != suffix[--suffix_len])			return NULL;	} 	if (path_len && !is_dir_sep(path[path_len - 1]))		return NULL;	return strndup(path, chomp_trailing_dir_sep(path, path_len));}