dmenu_path.c (shell is a bottleneck)

3 files changed, 108 insertions, 34 deletions

diff --git a/Makefile b/Makefile
index 1082697..c183779 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,7 @@
 
 include config.mk
 
-all: options dmenu
+all: options dmenu dmenu_path
 
 options:
         @echo dmenu build options:
@@ -11,22 +11,21 @@ options:
         @echo "LDFLAGS  = ${LDFLAGS}"
         @echo "CC       = ${CC}"
 
-dmenu.o: dmenu.c config.mk
-        @echo CC $<
-        @${CC} -c ${CFLAGS} $<
+dmenu: dmenu.c config.mk
+dmenu_path: dmenu_path.c
 
-dmenu: dmenu.o
+dmenu dmenu_path:
         @echo CC -o $@
-        @${CC} -o $@ $+ ${LDFLAGS}
+        @${CC} -o $@ $< ${CFLAGS} ${LDFLAGS}
 
 clean:
         @echo cleaning
-        @rm -f dmenu dmenu.o dmenu-${VERSION}.tar.gz
+        @rm -f dmenu dmenu_path dmenu-${VERSION}.tar.gz
 
 dist: clean
         @echo creating dist tarball
         @mkdir -p dmenu-${VERSION}
-        @cp LICENSE Makefile README config.mk dmenu.1 dmenu.c dmenu_path dmenu_run dmenu-${VERSION}
+        @cp LICENSE Makefile README config.mk dmenu.1 dmenu.c dmenu_path.c dmenu_run dmenu-${VERSION}
         @tar -cf dmenu-${VERSION}.tar dmenu-${VERSION}
         @gzip dmenu-${VERSION}.tar
         @rm -rf dmenu-${VERSION}
diff --git a/dmenu_path b/dmenu_path
deleted file mode 100755
index a9ddd47..0000000
--- a/dmenu_path
+++ /dev/null
@@ -1,26 +0,0 @@
-#!/bin/sh
-CACHE=$HOME/.dmenu_cache
-IFS=:
-
-uptodate() {
-        test -f "$CACHE" &&
-        for dir in $PATH
-        do
-                test ! $dir -nt "$CACHE" || return 1
-        done
-}
-
-if ! uptodate
-then
-        for dir in $PATH
-        do
-                cd "$dir" &&
-                for file in *
-                do
-                        test -x "$file" && echo "$file"
-                done
-        done | sort -u > "$CACHE".$$ &&
-        mv "$CACHE".$$ "$CACHE"
-fi
-
-cat "$CACHE"
diff --git a/dmenu_path.c b/dmenu_path.c
new file mode 100644
index 0000000..1575f1d
--- /dev/null
+++ b/dmenu_path.c
@@ -0,0 +1,101 @@
+/* See LICENSE file for copyright and license details. */
+#include <dirent.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#define CACHE ".dmenu_cache"
+
+static int qstrcmp(const void *a, const void *b);
+static void die(const char *s);
+static void scan(void);
+static int uptodate(void);
+
+static char **items = NULL;
+static const char *Home, *Path;
+static size_t count = 0;
+
+int
+main(void) {
+        if(!(Home = getenv("HOME")))
+                die("no $HOME");
+        if(!(Path = getenv("PATH")))
+                die("no $PATH");
+        if(chdir(Home) < 0)
+                die("chdir failed");
+        if(uptodate()) {
+                execlp("cat", "cat", CACHE, NULL);
+                die("exec failed");
+        }
+        scan();
+        return EXIT_SUCCESS;
+}
+
+void
+die(const char *s) {
+        fprintf(stderr, "dmenu_path: %s\n", s);
+        exit(EXIT_FAILURE);
+}
+
+int
+qstrcmp(const void *a, const void *b) {
+        return strcmp(*(const char **)a, *(const char **)b);
+}
+
+void
+scan(void) {
+        char buf[PATH_MAX];
+        char *dir, *path;
+        size_t i;
+        struct dirent *ent;
+        DIR *dp;
+        FILE *cache;
+
+        if(!(path = strdup(Path)))
+                die("strdup failed");
+        for(dir = strtok(path, ":"); dir; dir = strtok(NULL, ":")) {
+                if(!(dp = opendir(dir)))
+                        continue;
+                while((ent = readdir(dp))) {
+                        snprintf(buf, sizeof buf, "%s/%s", dir, ent->d_name);
+                        if(ent->d_name[0] == '.' || access(buf, X_OK) < 0)
+                                continue;
+                        if(!(items = realloc(items, ++count * sizeof *items)))
+                                die("malloc failed");
+                        if(!(items[count-1] = strdup(ent->d_name)))
+                                die("strdup failed");
+                }
+                closedir(dp);
+        }
+        qsort(items, count, sizeof *items, qstrcmp);
+        if(!(cache = fopen(CACHE, "w")))
+                die("open failed");
+        for(i = 0; i < count; i++) {
+                if(i > 0 && !strcmp(items[i], items[i-1]))
+                        continue;
+                fprintf(cache,  "%s\n", items[i]);
+                fprintf(stdout, "%s\n", items[i]);
+        }
+        fclose(cache);
+        free(path);
+}
+
+int
+uptodate(void) {
+        char *dir, *path;
+        time_t mtime;
+        struct stat st;
+
+        if(stat(CACHE, &st) < 0)
+                return 0;
+        mtime = st.st_mtime;
+        if(!(path = strdup(Path)))
+                die("strdup failed");
+        for(dir = strtok(path, ":"); dir; dir = strtok(NULL, ":"))
+                if(!stat(dir, &st) && st.st_mtime > mtime)
+                        return 0;
+        free(path);
+        return 1;
+}