1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * I'm tired of doing "vsnprintf()" etc just to open a
4*4882a593Smuzhiyun * file, so here's a "return static buffer with printf"
5*4882a593Smuzhiyun * interface for paths.
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * It's obviously not thread-safe. Sue me. But it's quite
8*4882a593Smuzhiyun * useful for doing things like
9*4882a593Smuzhiyun *
10*4882a593Smuzhiyun * f = open(mkpath("%s/%s.perf", base, name), O_RDONLY);
11*4882a593Smuzhiyun *
12*4882a593Smuzhiyun * which is what it's designed for.
13*4882a593Smuzhiyun */
14*4882a593Smuzhiyun #include "path.h"
15*4882a593Smuzhiyun #include "cache.h"
16*4882a593Smuzhiyun #include <linux/kernel.h>
17*4882a593Smuzhiyun #include <limits.h>
18*4882a593Smuzhiyun #include <stdio.h>
19*4882a593Smuzhiyun #include <string.h>
20*4882a593Smuzhiyun #include <sys/types.h>
21*4882a593Smuzhiyun #include <sys/stat.h>
22*4882a593Smuzhiyun #include <dirent.h>
23*4882a593Smuzhiyun #include <unistd.h>
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun static char bad_path[] = "/bad-path/";
26*4882a593Smuzhiyun /*
27*4882a593Smuzhiyun * One hack:
28*4882a593Smuzhiyun */
get_pathname(void)29*4882a593Smuzhiyun static char *get_pathname(void)
30*4882a593Smuzhiyun {
31*4882a593Smuzhiyun static char pathname_array[4][PATH_MAX];
32*4882a593Smuzhiyun static int idx;
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun return pathname_array[3 & ++idx];
35*4882a593Smuzhiyun }
36*4882a593Smuzhiyun
cleanup_path(char * path)37*4882a593Smuzhiyun static char *cleanup_path(char *path)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun /* Clean it up */
40*4882a593Smuzhiyun if (!memcmp(path, "./", 2)) {
41*4882a593Smuzhiyun path += 2;
42*4882a593Smuzhiyun while (*path == '/')
43*4882a593Smuzhiyun path++;
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun return path;
46*4882a593Smuzhiyun }
47*4882a593Smuzhiyun
mkpath(const char * fmt,...)48*4882a593Smuzhiyun char *mkpath(const char *fmt, ...)
49*4882a593Smuzhiyun {
50*4882a593Smuzhiyun va_list args;
51*4882a593Smuzhiyun unsigned len;
52*4882a593Smuzhiyun char *pathname = get_pathname();
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun va_start(args, fmt);
55*4882a593Smuzhiyun len = vsnprintf(pathname, PATH_MAX, fmt, args);
56*4882a593Smuzhiyun va_end(args);
57*4882a593Smuzhiyun if (len >= PATH_MAX)
58*4882a593Smuzhiyun return bad_path;
59*4882a593Smuzhiyun return cleanup_path(pathname);
60*4882a593Smuzhiyun }
61*4882a593Smuzhiyun
path__join(char * bf,size_t size,const char * path1,const char * path2)62*4882a593Smuzhiyun int path__join(char *bf, size_t size, const char *path1, const char *path2)
63*4882a593Smuzhiyun {
64*4882a593Smuzhiyun return scnprintf(bf, size, "%s%s%s", path1, path1[0] ? "/" : "", path2);
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun
path__join3(char * bf,size_t size,const char * path1,const char * path2,const char * path3)67*4882a593Smuzhiyun int path__join3(char *bf, size_t size, const char *path1, const char *path2, const char *path3)
68*4882a593Smuzhiyun {
69*4882a593Smuzhiyun return scnprintf(bf, size, "%s%s%s%s%s", path1, path1[0] ? "/" : "",
70*4882a593Smuzhiyun path2, path2[0] ? "/" : "", path3);
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun
is_regular_file(const char * file)73*4882a593Smuzhiyun bool is_regular_file(const char *file)
74*4882a593Smuzhiyun {
75*4882a593Smuzhiyun struct stat st;
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun if (stat(file, &st))
78*4882a593Smuzhiyun return false;
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun return S_ISREG(st.st_mode);
81*4882a593Smuzhiyun }
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun /* Helper function for filesystems that return a dent->d_type DT_UNKNOWN */
is_directory(const char * base_path,const struct dirent * dent)84*4882a593Smuzhiyun bool is_directory(const char *base_path, const struct dirent *dent)
85*4882a593Smuzhiyun {
86*4882a593Smuzhiyun char path[PATH_MAX];
87*4882a593Smuzhiyun struct stat st;
88*4882a593Smuzhiyun
89*4882a593Smuzhiyun sprintf(path, "%s/%s", base_path, dent->d_name);
90*4882a593Smuzhiyun if (stat(path, &st))
91*4882a593Smuzhiyun return false;
92*4882a593Smuzhiyun
93*4882a593Smuzhiyun return S_ISDIR(st.st_mode);
94*4882a593Smuzhiyun }
95