Add getlinex()

lib/commonio.c

@@ -447,7 +447,7 @@ static void add_one_entry_nis (struct commonio_db *db,
 
 int commonio_open (struct commonio_db *db, int mode)
 {
-	char *buf;
+	char *buf = NULL;
 	char *cp;
 	char *line;
 	struct commonio_entry *p;
@@ -512,34 +512,7 @@ int commonio_open (struct commonio_db *db, int mode)
 	/* Do not inherit fd in spawned processes (e.g. nscd) */
 	fcntl (fileno (db->fp), F_SETFD, FD_CLOEXEC);
 
-	buflen = BUFLEN;
-	buf = (char *) malloc (buflen);
-	if (NULL == buf) {
-		goto cleanup_ENOMEM;
-	}
-
-	while (db->ops->fgets (buf, (int) buflen, db->fp) == buf) {
-		while (   ((cp = strrchr (buf, '\n')) == NULL)
-		       && (feof (db->fp) == 0)) {
-			size_t len;
-
-			buflen += BUFLEN;
-			cp = (char *) realloc (buf, buflen);
-			if (NULL == cp) {
-				goto cleanup_buf;
-			}
-			buf = cp;
-			len = strlen (buf);
-			if (db->ops->fgets (buf + len,
-			                    (int) (buflen - len),
-			                    db->fp) == NULL) {
-				goto cleanup_buf;
-			}
-		}
-		cp = strrchr (buf, '\n');
-		if (NULL != cp) {
-			*cp = '\0';
-		}
+	while (db->ops->getline (&buf, &buflen, db->fp) != -1) {
 
 		line = strdup (buf);
 		if (NULL == line) {

lib/commonio.h

@@ -58,11 +58,12 @@ struct commonio_ops {
 	int (*put) (const void *, FILE *);
 
 	/*
-	 * fgets and fputs (can be replaced by versions that
+	 * fgets, fputs, and getline (can be replaced by versions that
 	 * understand line continuation conventions).
 	 */
 	/*@null@*/char *(*fgets) (/*@returned@*/ /*@out@*/char *s, int n, FILE *stream);
 	int (*fputs) (const char *, FILE *);
+	ssize_t (*getline) (char **restrict lineptr, size_t *restrict size, FILE *restrict stream);
 
 	/*
 	 * open_hook and close_hook.

lib/fputsx.c

@@ -16,6 +16,55 @@
 #ident "$Id$"
 
 
+/*
+ * Similar to getline(3), but handle escaped newlines.
+ * Returns the length of the string, or -1 on error.
+ */
+ssize_t
+getlinex(char **restrict lineptr, size_t *restrict size,
+         FILE *restrict stream)
+{
+	char    *p;
+	size_t  len;
+
+	if (*lineptr == NULL || *size < BUFSIZ) {
+		*size = BUFSIZ;
+	} else if (*size > INT_MAX) {
+		*size = INT_MAX;
+	}
+
+	len = 0;
+	for (size_t sz = *size; sz < INT_MAX; sz <<= 1) {
+		*size = sz;
+		*lineptr = reallocf(*lineptr, sz);
+		if (*lineptr == NULL)
+			return -1;
+
+		p = fgetsnulx(*lineptr + len, sz, stream);
+		if (p == NULL)
+			return -1;
+
+		len = p - *lineptr;
+		if (p[-1] == '\n' && p[-2] != '\\')
+			return len;
+		if (p[-1] == '\n' && p[-2] == '\\')
+			len -= 2;
+	}
+
+	return -1;
+}
+
+
+/* Like fgetsx(), but returns a pointer to the terminating NUL byte.  */
+char *
+fgetsnulx(char *buf, int size, FILE *stream)
+{
+	if (fgetsx(buf, size, stream) == NULL)
+		return NULL;
+	return buf + strlen(buf);
+}
+
+
 /*@null@*/char *fgetsx (/*@returned@*/ /*@out@*/char *buf, int cnt, FILE * f)
 {
 	char *cp = buf;

lib/groupio.c

@@ -96,6 +96,7 @@ static struct commonio_ops group_ops = {
 	group_put,
 	fgetsx,
 	fputsx,
+	getlinex,		/* getline */
 	group_open_hook,
 	group_close_hook
 };

lib/gshadow.c

@@ -192,48 +192,16 @@ void endsgent (void)
 	static size_t buflen = 0;
 	static char *buf = NULL;
 
-	char *cp;
-
-	if (0 == buflen) {
-		buf = (char *) malloc (BUFSIZ);
-		if (NULL == buf) {
-			return NULL;
-		}
-		buflen = BUFSIZ;
-	}
-
 	if (NULL == fp) {
 		return NULL;
 	}
 
 #ifdef	USE_NIS
-	while (fgetsx (buf, (int) buflen, fp) == buf)
+	while (getlinex (&buf, &buflen, fp) != -1)
 #else
-	if (fgetsx (buf, (int) buflen, fp) == buf)
+	if (getlinex (&buf, &buflen, fp) != -1)
 #endif
 	{
-		while (   ((cp = strrchr (buf, '\n')) == NULL)
-		       && (feof (fp) == 0)) {
-			size_t len;
-
-			cp = (char *) realloc (buf, buflen*2);
-			if (NULL == cp) {
-				return NULL;
-			}
-			buf = cp;
-			buflen *= 2;
-
-			len = strlen (buf);
-			if (fgetsx (&buf[len],
-			            (int) (buflen - len),
-			            fp) != &buf[len]) {
-				return NULL;
-			}
-		}
-		cp = strrchr (buf, '\n');
-		if (NULL != cp) {
-			*cp = '\0';
-		}
 #ifdef	USE_NIS
 		if (nis_ignore && IS_NISCHAR (buf[0])) {
 			continue;

lib/prototypes.h

@@ -176,6 +176,9 @@ extern int get_uid (const char *uidstr, uid_t *uid);
 extern int getulong (const char *numstr, /*@out@*/unsigned long int *result);
 
 /* fputsx.c */
+extern ssize_t getlinex(char **restrict lineptr, size_t *restrict size,
+    FILE *restrict stream);
+extern char * fgetsnulx(char *buf, int size, FILE *stream);
 extern /*@null@*/char *fgetsx (/*@returned@*/ /*@out@*/char *, int, FILE *);
 extern int fputsx (const char *, FILE *);
 

lib/pwio.c

@@ -74,6 +74,7 @@ static struct commonio_ops passwd_ops = {
 	passwd_put,
 	fgets,
 	fputs,
+	getline,		/* getline */
 	NULL,			/* open_hook */
 	NULL			/* close_hook */
 };

lib/sgroupio.c

@@ -195,6 +195,7 @@ static struct commonio_ops gshadow_ops = {
 	gshadow_put,
 	fgetsx,
 	fputsx,
+	getlinex,		/* getline */
 	NULL,			/* open_hook */
 	NULL			/* close_hook */
 };

lib/shadowio.c

@@ -73,6 +73,7 @@ static struct commonio_ops shadow_ops = {
 	shadow_put,
 	fgets,
 	fputs,
+	getline,		/* getline */
 	NULL,			/* open_hook */
 	NULL			/* close_hook */
 };

lib/subordinateio.c

@@ -145,6 +145,7 @@ static struct commonio_ops subordinate_ops = {
 	subordinate_put,	/* put */
 	fgets,			/* fgets */
 	fputs,			/* fputs */
+	getline,		/* getline */
 	NULL,			/* open_hook */
 	NULL,			/* close_hook */
 };