* vim:ts=4:sw=4:expandtab
*
* i3 - an improved dynamic tiling window manager
- * © 2009-2011 Michael Stapelberg and contributors (see also: LICENSE)
+ * © 2009 Michael Stapelberg and contributors (see also: LICENSE)
*
*/
+#include "libi3.h"
+
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
+#include <errno.h>
+#include <inttypes.h>
#include <i3/ipc.h>
-#include "libi3.h"
-
/*
* Reads a message from the given socket file descriptor and stores its length
* (reply_length) as well as a pointer to its contents (reply).
*
* Returns -1 when read() fails, errno will remain.
- * Returns -2 when the IPC protocol is violated (invalid magic, unexpected
+ * Returns -2 on EOF.
+ * Returns -3 when the IPC protocol is violated (invalid magic, unexpected
* message type, EOF instead of a message). Additionally, the error will be
* printed to stderr.
* Returns 0 on success.
*
*/
-int ipc_recv_message(int sockfd, uint32_t message_type,
+int ipc_recv_message(int sockfd, uint32_t *message_type,
uint32_t *reply_length, uint8_t **reply) {
/* Read the message header first */
- uint32_t to_read = strlen(I3_IPC_MAGIC) + sizeof(uint32_t) + sizeof(uint32_t);
+ const uint32_t to_read = strlen(I3_IPC_MAGIC) + sizeof(uint32_t) + sizeof(uint32_t);
char msg[to_read];
char *walk = msg;
uint32_t read_bytes = 0;
while (read_bytes < to_read) {
- int n = read(sockfd, msg + read_bytes, to_read);
+ int n = read(sockfd, msg + read_bytes, to_read - read_bytes);
if (n == -1)
return -1;
if (n == 0) {
- fprintf(stderr, "IPC: received EOF instead of reply\n");
- return -2;
+ if (read_bytes == 0) {
+ return -2;
+ } else {
+ ELOG("IPC: unexpected EOF while reading header, got %" PRIu32 " bytes, want %" PRIu32 " bytes\n",
+ read_bytes, to_read);
+ return -3;
+ }
}
read_bytes += n;
- to_read -= n;
}
if (memcmp(walk, I3_IPC_MAGIC, strlen(I3_IPC_MAGIC)) != 0) {
- fprintf(stderr, "IPC: invalid magic in reply\n");
- return -2;
+ ELOG("IPC: invalid magic in header, got \"%.*s\", want \"%s\"\n",
+ (int)strlen(I3_IPC_MAGIC), walk, I3_IPC_MAGIC);
+ return -3;
}
walk += strlen(I3_IPC_MAGIC);
- *reply_length = *((uint32_t*)walk);
+ memcpy(reply_length, walk, sizeof(uint32_t));
walk += sizeof(uint32_t);
- if (*((uint32_t*)walk) != message_type) {
- fprintf(stderr, "IPC: unexpected reply type (got %d, expected %d)\n", *((uint32_t*)walk), message_type);
- return -2;
- }
+ if (message_type != NULL)
+ memcpy(message_type, walk, sizeof(uint32_t));
*reply = smalloc(*reply_length);
- to_read = *reply_length;
read_bytes = 0;
- while (read_bytes < to_read) {
- int n = read(sockfd, *reply + read_bytes, to_read);
- if (n == -1)
+ while (read_bytes < *reply_length) {
+ const int n = read(sockfd, *reply + read_bytes, *reply_length - read_bytes);
+ if (n == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
return -1;
+ }
+ if (n == 0) {
+ ELOG("IPC: unexpected EOF while reading payload, got %" PRIu32 " bytes, want %" PRIu32 " bytes\n",
+ read_bytes, *reply_length);
+ return -3;
+ }
read_bytes += n;
- to_read -= n;
}
return 0;