strbuf_readlink: support link targets that exceed PATH_MAX

kblees · dscho · commit 41f0299186dd · 2019-05-13T22:56:47.000+02:00
strbuf_readlink() refuses to read link targets that exceed PATH_MAX (even
if a sufficient size was specified by the caller).

As some platforms support longer paths, remove this restriction (similar
to strbuf_getcwd()).

Signed-off-by: Karsten Blees &lt;blees@dcon.de&gt;
diff --git a/strbuf.c b/strbuf.c
@@ -519,16 +519,14 @@ ssize_t strbuf_write(struct strbuf *sb, FILE *f)
 }
 
 
-#define STRBUF_MAXLINK (2*PATH_MAX)
-
 int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
 {
 	size_t oldalloc = sb->alloc;
 
 	if (hint < 32)
 		hint = 32;
 
-	while (hint < STRBUF_MAXLINK) {
+	for (;;) {
 		ssize_t len;
 
 		strbuf_grow(sb, hint + 1);

Original file line number	Diff line number	Diff line change
`@@ -519,16 +519,14 @@ ssize_t strbuf_write(struct strbuf sb, FILE f)`
`519`	`519`	`}`
`520`	`520`
`521`	`521`
`522`		`-#define STRBUF_MAXLINK (2*PATH_MAX)`
`523`		`-`
`524`	`522`	`int strbuf_readlink(struct strbuf sb, const char path, size_t hint)`
`525`	`523`	`{`
`526`	`524`	`size_t oldalloc = sb->alloc;`
`527`	`525`
`528`	`526`	`if (hint < 32)`
`529`	`527`	`hint = 32;`
`530`	`528`
`531`		`- while (hint < STRBUF_MAXLINK) {`
	`529`	`+ for (;;) {`
`532`	`530`	`ssize_t len;`
`533`	`531`
`534`	`532`	`strbuf_grow(sb, hint + 1);`