ed

commit 5b51c335a0e4642ea15aca1b66fae95c242e687d
parent 99e4f82543be7a4ebafa993e17acbf0ee3c90ec9
Author: Roberto E. Vargas Caballero <k0ga@shike2.com>
Date:   Tue,  1 Dec 2015 21:31:55 +0100

Avoid memory and file leak in doread()

inject() can call to error(), and there is also a direct
call to error() in doread(), and we are open and allocating
memory there, so we can have memory leaks there. The best
option is making statics s and fp and then the memory
leaks will be controlled in the next iteration.

Diffstat:
M
ed.c
 | 
22
++++++++++++----------

1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/ed.c b/ed.c
@@ -448,34 +448,36 @@ dowrite(char *fname, int trunc)
 static void
 doread(char *fname)
 {
-	FILE *fp;
 	size_t len = 0, cnt;
 	ssize_t n;
-	char *s = NULL, *p;
+	char *p;
+	FILE *aux;
+	static char *s;
+	static FILE *fp;
 
+	if (fp)
+		fclose(fp);
 	if (!savfname)
 		setfname(fname);
 	if (!(fp = fopen(fname, "r")))
 		error("input/output error");
+
 	curln = line2;
 	for (cnt = 0; (n = getline(&s, &len, fp)) > 0; cnt += (size_t)n) {
 		if (s[n-1] != '\n') {
-			if (len == SIZE_MAX ||
-			    !(p = realloc(s, ++len)))
+			if (len == SIZE_MAX || !(p = realloc(s, ++len)))
 				error("out of memory");
 			s = p;
 			s[n-1] = '\n';
 			s[n] = '\0';
 		}
-		/*
-		 * FIXME: if inject calls error we can have a
-		 *        memory leak, and a file leak
-		 */
 		inject(s);
 	}
 	printf("%zu\n", cnt);
-	free(s);
-	if (fclose(fp))
+
+	aux = fp;
+	fp = NULL;
+	if (fclose(aux))
 		error("input/output error");
 }