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.
This commit is contained in:
Wolfgang Corcoran-Mathe 2015-08-28 00:10:02 -04:00 committed by sin
parent 1fa942a0ee
commit 438d2542e4

5
tail.c
View File

@ -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) {