errors: add GIT_EEOF to indicate early EOFcmn/server-errors

This can be used by tools to show mesages about failing to communicate
with the server. The error message in this case will often contain the
server's error message, as far as it managed to send anything.

5 files changed, 15 insertions, 4 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ad127aa55..8a0ae0e03 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -93,6 +93,11 @@ support for HTTPS connections insead of OpenSSL.
 * `git_stash_pop()` will apply a stashed state (like `git_stash_apply()`)
   but will remove the stashed state after a successful application.
 
+* A new error code `GIT_EEOF` indicates an early EOF from the
+  server. This typically indicates an error with the URL or
+  configuration of the server, and tools can use this to show messages
+  about failing to communicate with the server.
+
 ### API removals
 
 * `git_remote_save()` and `git_remote_clear_refspecs()` has been
diff --git a/include/git2/errors.h b/include/git2/errors.h
index ef4fabb7d..31fc6035a 100644
--- a/include/git2/errors.h
+++ b/include/git2/errors.h
@@ -45,6 +45,7 @@ typedef enum {
 	GIT_ECERTIFICATE    = -17,      /**< Server certificate is invalid */
 	GIT_EAPPLIED        = -18,	/**< Patch/merge has already been applied */
 	GIT_EPEEL           = -19,      /**< The requested peel operation is not possible */
+	GIT_EEOF            = -20,      /**< Unexpected EOF */
 
 	GIT_PASSTHROUGH     = -30,	/**< Internal only */
 	GIT_ITEROVER        = -31,	/**< Signals end of iteration with iterator */
diff --git a/src/openssl_stream.c b/src/openssl_stream.c
index 2ebfac738..78f705e49 100644
--- a/src/openssl_stream.c
+++ b/src/openssl_stream.c
@@ -55,6 +55,7 @@ static int ssl_set_error(SSL *ssl, int error)
 			break;
 		}
 		giterr_set(GITERR_NET, "SSL error: received early EOF");
+		return GIT_EEOF;
 		break;
 	case SSL_ERROR_SSL:
 		e = ERR_get_error();
diff --git a/src/transports/smart_protocol.c b/src/transports/smart_protocol.c
index 66f78f73c..0920f2eef 100644
--- a/src/transports/smart_protocol.c
+++ b/src/transports/smart_protocol.c
@@ -52,7 +52,7 @@ int git_smart__store_refs(transport_smart *t, int flushes)
 
 			if (recvd == 0 && !flush) {
 				giterr_set(GITERR_NET, "early EOF");
-				return -1;
+				return GIT_EEOF;
 			}
 
 			continue;
@@ -770,7 +770,7 @@ static int parse_report(transport_smart *transport, git_push *push)
 
 			if (recvd == 0) {
 				giterr_set(GITERR_NET, "early EOF");
-				return -1;
+				return GIT_EEOF;
 			}
 			continue;
 		}
diff --git a/src/transports/ssh.c b/src/transports/ssh.c
index 0d179e715..55f715b1d 100644
--- a/src/transports/ssh.c
+++ b/src/transports/ssh.c
@@ -129,10 +129,14 @@ static int ssh_stream_read(
 		return -1;
 	}
 
-	/* Having something in stderr is typically a not-found error */
+	/*
+	 * If we can't get anything out of stdout, it's typically a
+	 * not-found error, so read from stderr and signal EOF on
+	 * stderr.
+	 */
 	if (rc == 0 && (rc = libssh2_channel_read_stderr(s->channel, buffer, buf_size)) > 0) {
 		giterr_set(GITERR_SSH, "%*s", rc, buffer);
-		return -1;
+		return GIT_EEOF;
 	}