ap

commit 3881495ad1755faadda166e250e44967e2a25f95
parent 52bb19476ac4dae399ad5029215d8dcb61dc77a0
Author: Jacob R. Edwards <n/a>
Date:   Sun,  9 Oct 2022 09:23:32 -0700

Introduce a standard interface to shifting buffer contents

Diffstat:
M
aps/aps.c
 | 
6
++----
M
lib/ap/buf.c
 | 
12
++++++++++++
M
lib/ap/buf.h
 | 
1
+
M
lib/ap/client.c
 | 
3
+--

4 files changed, 16 insertions(+), 6 deletions(-)
diff --git a/aps/aps.c b/aps/aps.c
@@ -160,8 +160,7 @@ aps_respond(struct aps *aps, int fd)
 			buf->len = 0;
 			aps->pfds[fd].events = POLLIN;
 		} else {
-			memmove(buf->data, buf->data + n, buf->len - n);
-			buf->len -= n;
+			bufshift(buf, n);
 		}
 		return 0;
 	}
@@ -280,8 +279,7 @@ aps_command(struct aps *aps, int s)
 
 exit:
 	len = next - (char *)buf->data;
-	memmove(buf->data, buf->data + len, buf->len - len);
-	buf->len -= len;
+	bufshift(buf, len);
 
 	free(argv);
 	return aps_bufstatus(aps, s, status);
diff --git a/lib/ap/buf.c b/lib/ap/buf.c
@@ -93,6 +93,18 @@ bufappend(struct buf *buf, void *data, size_t len)
 }
 
 int
+bufshift(struct buf *buf, size_t n)
+{
+	if (n > buf->len) {
+		errno = EOVERFLOW;
+		return 1;
+	}
+	memmove(buf->data, buf->data + n, buf->len - n);
+	buf->len -= n;
+	return 0;
+}
+
+int
 bufword(struct buf *buf, char *word)
 {
 	size_t len;
diff --git a/lib/ap/buf.h b/lib/ap/buf.h
@@ -9,5 +9,6 @@ void	buffree(struct buf *);
 int	bufresize(struct buf *, size_t);
 int	bufenlarge(struct buf *, size_t);
 int	bufappend(struct buf *, void *, size_t);
+int	bufshift(struct buf *, size_t);
 int	bufword(struct buf *, char *);
 int	bufline(struct buf *, char *);
diff --git a/lib/ap/client.c b/lib/ap/client.c
@@ -115,8 +115,7 @@ apc_read(struct apc *apc)
 	memcpy(buf, apc->response->data, len);
 	buf[len] = 0;
 
-	memmove(apc->response->data, end + 1,
-	    apc->response->len -= len + 1);
+	bufshift(apc->response, len + 1);
 
 	if (strcmp(buf, "ok") == 0 || strncmp(buf, "error: ", 7) == 0) {
 		if (*buf == 'e') {