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 "cache.h"
  15#include "path.h"
  16#include <linux/kernel.h>
  17#include <limits.h>
  18#include <stdio.h>
  19#include <sys/types.h>
  20#include <sys/stat.h>
  21#include <dirent.h>
  22#include <unistd.h>
  23
  24static char bad_path[] = "/bad-path/";
  25/*
  26 * One hack:
  27 */
  28static char *get_pathname(void)
  29{
  30        static char pathname_array[4][PATH_MAX];
  31        static int idx;
  32
  33        return pathname_array[3 & ++idx];
  34}
  35
  36static char *cleanup_path(char *path)
  37{
  38        /* Clean it up */
  39        if (!memcmp(path, "./", 2)) {
  40                path += 2;
  41                while (*path == '/')
  42                        path++;
  43        }
  44        return path;
  45}
  46
  47char *mkpath(const char *fmt, ...)
  48{
  49        va_list args;
  50        unsigned len;
  51        char *pathname = get_pathname();
  52
  53        va_start(args, fmt);
  54        len = vsnprintf(pathname, PATH_MAX, fmt, args);
  55        va_end(args);
  56        if (len >= PATH_MAX)
  57                return bad_path;
  58        return cleanup_path(pathname);
  59}
  60
  61int path__join(char *bf, size_t size, const char *path1, const char *path2)
  62{
  63        return scnprintf(bf, size, "%s%s%s", path1, path1[0] ? "/" : "", path2);
  64}
  65
  66int path__join3(char *bf, size_t size, const char *path1, const char *path2, const char *path3)
  67{
  68        return scnprintf(bf, size, "%s%s%s%s%s", path1, path1[0] ? "/" : "",
  69                         path2, path2[0] ? "/" : "", path3);
  70}
  71
  72bool is_regular_file(const char *file)
  73{
  74        struct stat st;
  75
  76        if (stat(file, &st))
  77                return false;
  78
  79        return S_ISREG(st.st_mode);
  80}
  81
  82/* Helper function for filesystems that return a dent->d_type DT_UNKNOWN */
  83bool is_directory(const char *base_path, const struct dirent *dent)
  84{
  85        char path[PATH_MAX];
  86        struct stat st;
  87
  88        sprintf(path, "%s/%s", base_path, dent->d_name);
  89        if (stat(path, &st))
  90                return false;
  91
  92        return S_ISDIR(st.st_mode);
  93}
  94