LXR linux/tools/perf/util/path.c

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