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	readstdin: reduce memory-usage by duplicating the line from getline() - dmenu -…
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	---
	commit dfbbf7f6e1b22ccf9e5a45d77ee10995577fb4fc
	parent ba1a347dcaba055f824161007dfee60db3ea785b
	Author: Hiltjo Posthuma <[email protected]>
	Date: Wed, 8 Mar 2023 21:20:52 +0100

	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.

	Diffstat:
	M dmenu.c \| 9 +++++----

	1 file changed, 5 insertions(+), 4 deletions(-)
	---
	diff --git a/dmenu.c b/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)