dmenu_path.c (shell is a bottleneck)
[dmenu.git] / dmenu_path.c
1 /* See LICENSE file for copyright and license details. */
2 #include <dirent.h>
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <string.h>
6 #include <unistd.h>
7 #include <sys/stat.h>
8
9 #define CACHE ".dmenu_cache"
10
11 static int qstrcmp(const void *a, const void *b);
12 static void die(const char *s);
13 static void scan(void);
14 static int uptodate(void);
15
16 static char **items = NULL;
17 static const char *Home, *Path;
18 static size_t count = 0;
19
20 int
21 main(void) {
22         if(!(Home = getenv("HOME")))
23                 die("no $HOME");
24         if(!(Path = getenv("PATH")))
25                 die("no $PATH");
26         if(chdir(Home) < 0)
27                 die("chdir failed");
28         if(uptodate()) {
29                 execlp("cat", "cat", CACHE, NULL);
30                 die("exec failed");
31         }
32         scan();
33         return EXIT_SUCCESS;
34 }
35
36 void
37 die(const char *s) {
38         fprintf(stderr, "dmenu_path: %s\n", s);
39         exit(EXIT_FAILURE);
40 }
41
42 int
43 qstrcmp(const void *a, const void *b) {
44         return strcmp(*(const char **)a, *(const char **)b);
45 }
46
47 void
48 scan(void) {
49         char buf[PATH_MAX];
50         char *dir, *path;
51         size_t i;
52         struct dirent *ent;
53         DIR *dp;
54         FILE *cache;
55
56         if(!(path = strdup(Path)))
57                 die("strdup failed");
58         for(dir = strtok(path, ":"); dir; dir = strtok(NULL, ":")) {
59                 if(!(dp = opendir(dir)))
60                         continue;
61                 while((ent = readdir(dp))) {
62                         snprintf(buf, sizeof buf, "%s/%s", dir, ent->d_name);
63                         if(ent->d_name[0] == '.' || access(buf, X_OK) < 0)
64                                 continue;
65                         if(!(items = realloc(items, ++count * sizeof *items)))
66                                 die("malloc failed");
67                         if(!(items[count-1] = strdup(ent->d_name)))
68                                 die("strdup failed");
69                 }
70                 closedir(dp);
71         }
72         qsort(items, count, sizeof *items, qstrcmp);
73         if(!(cache = fopen(CACHE, "w")))
74                 die("open failed");
75         for(i = 0; i < count; i++) {
76                 if(i > 0 && !strcmp(items[i], items[i-1]))
77                         continue;
78                 fprintf(cache,  "%s\n", items[i]);
79                 fprintf(stdout, "%s\n", items[i]);
80         }
81         fclose(cache);
82         free(path);
83 }
84
85 int
86 uptodate(void) {
87         char *dir, *path;
88         time_t mtime;
89         struct stat st;
90
91         if(stat(CACHE, &st) < 0)
92                 return 0;
93         mtime = st.st_mtime;
94         if(!(path = strdup(Path)))
95                 die("strdup failed");
96         for(dir = strtok(path, ":"); dir; dir = strtok(NULL, ":"))
97                 if(!stat(dir, &st) && st.st_mtime > mtime)
98                         return 0;
99         free(path);
100         return 1;
101 }