Commit Diff

Commit:
dfbbf7f6e1b22ccf9e5a45d77ee10995577fb4fc
From:
Hiltjo Posthuma <hiltjo@codemadness.org>
Date:
Message:
readstdin: reduce memory-usage by duplicating the line from getline() Improves upon commit 32db2b125190d366be472ccb7cad833248696144 The getline() implementation often uses a more greedy way of allocating memory. Using this buffer directly and forcing an allocation (by setting it to NULL) would waste a bit of extra space, depending on the implementation of course. Tested on musl libc and glibc. The current glibc version allocates a minimum of 120 bytes per line. For smaller lines musl libc seems less wasteful but still wastes a few bytes per line. On a dmenu_path listing on my system the memory usage was about 350kb (old) vs 30kb (new) on Void Linux glibc. Side-note that getline() also reads NUL bytes in lines, while strdup() would read until the NUL byte. Since dmenu reads text lines either is probably fine(tm). Also rename junk to linesiz.
Actions:
Patch | Tree
commit - ba1a347dcaba055f824161007dfee60db3ea785b
commit + dfbbf7f6e1b22ccf9e5a45d77ee10995577fb4fc
blob - 27b7a30f0af26ef5d3c0e72c318673c38ab72150
blob + 4e7df12eee673974038aeefeb2daa4bd8a8a2e60
--- dmenu.c
+++ dmenu.c
@@ -550,11 +550,11 @@ static void
 readstdin(void)
 {
 	char *line = NULL;
-	size_t i, junk, itemsiz = 0;
+	size_t i, itemsiz = 0, linesiz = 0;
 	ssize_t len;
 
 	/* read each line from stdin and add it to the item list */
-	for (i = 0; (len = getline(&line, &junk, stdin)) != -1; i++) {
+	for (i = 0; (len = getline(&line, &linesiz, stdin)) != -1; i++) {
 		if (i + 1 >= itemsiz) {
 			itemsiz += 256;
 			if (!(items = realloc(items, itemsiz * sizeof(*items))))
@@ -562,9 +562,10 @@ readstdin(void)
 		}
 		if (line[len - 1] == '\n')
 			line[len - 1] = '\0';
-		items[i].text = line;
+		if (!(items[i].text = strdup(line)))
+			die("strdup:");
+
 		items[i].out = 0;
-		line = NULL; /* next call of getline() allocates a new line */
 	}
 	free(line);
 	if (items)