commit 438d2542e4bb731c65d10f908cd0519cf502750c
Author: Wolfgang Corcoran-Mathe <[email protected]>
AuthorDate: Fri Aug 28 00:10:02 2015 -0400
Commit: sin <[email protected]>
CommitDate: Sun Aug 30 18:36:19 2015 +0100
tail: Don't print garbage when input contains no newlines.
getline(3) expects newline-terminated input. While glibc's
implementation seems to catch unterminated input and zero the
buffer, other versions (notably musl's) do not.
This is a workaround. Garbage will still be read, but
not printed.
diff --git a/tail.c b/tail.c
index 306bbc1..417289f 100644
--- a/tail.c
+++ b/tail.c
@@ -39,6 +39,7 @@ taketail(FILE *fp, const char *str, size_t n)
Rune *r = NULL;
char **ring = NULL;
size_t i, j, *size = NULL;
+ int seenln = 0;
if (!n)
return;
@@ -47,7 +48,7 @@ taketail(FILE *fp, const char *str, size_t n)
ring = ecalloc(n, sizeof(*ring));
size = ecalloc(n, sizeof(*size));
- for (i = j = 0; getline(ring + i, size + i, fp) > 0; )
+ for (i = j = 0; getline(ring + i, size + i, fp) > 0; seenln = 1)
i = j = (i + 1) % n;
} else {
r = ecalloc(n, sizeof(*r));
@@ -59,7 +60,7 @@ taketail(FILE *fp, const char *str, size_t n)
eprintf("%s: read error:", str);
do {
- if (ring && ring[j]) {
+ if (seenln && ring && ring[j]) {
fputs(ring[j], stdout);
free(ring[j]);
} else if (r) {
