Change amqp_error_string() to ret static strings

This is an API/ABI break.

1 files changed, 71 insertions, 21 deletions

diff --git a/librabbitmq/amqp_api.c b/librabbitmq/amqp_api.c
index cab0f4b..9f65c4c 100644
--- a/librabbitmq/amqp_api.c
+++ b/librabbitmq/amqp_api.c
@@ -46,34 +46,84 @@
 #include <stdlib.h>
 #include <string.h>
 
-static const char *client_error_strings[] = {
-  "operation completed successfully",   /* AMQP_STATUS_OK */
-  "could not allocate memory",          /* AMQP_STATUS_NO_MEMORY */
-  "received bad AMQP data",             /* AMQP_STATUS_BAD_AQMP_DATA */
-  "unknown AMQP class id",              /* AMQP_STATUS_UNKNOWN_CLASS */
-  "unknown AMQP method id",             /* AMQP_STATUS_UNKNOWN_METHOD */
-  "hostname lookup failed",             /* AMQP_STATUS_GETHOSTBYNAME_FAILED */
-  "incompatible AMQP version",          /* AMQP_STATUS_INCOMPATIBLE_AMQP_VERSION */
-  "connection closed unexpectedly",     /* AMQP_STATUS_CONNECTION_CLOSED */
-  "could not parse AMQP URL",           /* AMQP_STATUS_BAD_AMQP_URL */
-  "a socket error occurred",            /* AMQP_STATUS_SOCKET_ERROR */
-  "a SSL error occurred"                /* AMQP_STATUS_SSL_ERROR */
+#define ERROR_MASK (0x00FF)
+#define ERROR_CATEGORY_MASK (0xFF00)
+
+enum error_category_enum_ {
+  EC_base = 0,
+  EC_tcp = 1,
+  EC_ssl = 2
+};
+
+static const char *base_error_strings[] = {
+  "operation completed successfully",   /* AMQP_STATUS_OK                       0x0 */
+  "could not allocate memory",          /* AMQP_STATUS_NO_MEMORY                -0x0001 */
+  "invalid AMQP data",                  /* AMQP_STATUS_BAD_AQMP_DATA            -0x0002 */
+  "unknown AMQP class id",              /* AMQP_STATUS_UNKNOWN_CLASS            -0x0003 */
+  "unknown AMQP method id",             /* AMQP_STATUS_UNKNOWN_METHOD           -0x0004 */
+  "hostname lookup failed",             /* AMQP_STATUS_HOSTNAME_RESOLUTION_FAILED -0x0005 */
+  "incompatible AMQP version",          /* AMQP_STATUS_INCOMPATIBLE_AMQP_VERSION -0x0006 */
+  "connection closed unexpectedly",     /* AMQP_STATUS_CONNECTION_CLOSED        -0x0007 */
+  "could not parse AMQP URL",           /* AMQP_STATUS_BAD_AMQP_URL             -0x0008 */
+  "a socket error occurred",            /* AMQP_STATUS_SOCKET_ERROR             -0x0009 */
+  "invalid parameter",                  /* AMQP_STATUS_INVALID_PARAMETER        -0x000A */
+  "table too large for buffer",         /* AMQP_STATUS_TABLE_TOO_BIG            -0x000B */
+  "unexpected method received"          /* AMQP_STATUS_WRONG_METHOD             -0x000C */
+};
+
+static const char *tcp_error_strings[] = {
+  "a socket error occurred",              /* AMQP_STATUS_TCP_ERROR                -0x0100 */
+  "socket library initialization failed"  /* AMQP_STATUS_TCP_SOCKETLIB_INIT_ERROR -0x0101 */
+};
+
+static const char *ssl_error_strings[] = {
+  "a SSL error occurred",                 /* AMQP_STATUS_SSL_ERROR                -0x0200 */
+  "SSL hostname verification failed",     /* AMQP_STATUS_SSL_HOSTNAME_VERIFY_FAILED -0x0201 */
+  "SSL peer cert verification failed",    /* AMQP_STATUS_SSL_PEER_VERIFY_FAILED -0x0202 */
+  "SSL handshake failed"                  /* AMQP_STATUS_SSL_CONNECTION_FAILED  -0x0203 */
 };
 
-char *amqp_error_string(int err)
+static const char *unknown_error_string = "(unknown error)";
+
+const char *amqp_error_string(int code)
 {
-  const char *str;
-  const int max_error_index = sizeof(client_error_strings) / sizeof(char *);
+  const char *error_string;
+  size_t category = (((-code) & ERROR_CATEGORY_MASK) >> 16);
+  size_t error = (-code) & ERROR_MASK;
+
+  switch (category) {
+    case EC_base:
+      if (error < (sizeof(base_error_strings) / sizeof(char *))) {
+        error_string = base_error_strings[error];
+      } else {
+        error_string = unknown_error_string;
+      }
+      break;
+
+    case EC_tcp:
+      if (error < (sizeof(tcp_error_strings) / sizeof(char *))) {
+        error_string = tcp_error_strings[error];
+      } else {
+        error_string = unknown_error_string;
+      }
+      break;
+
+    case EC_ssl:
+      if (error < (sizeof(ssl_error_strings) / sizeof(char *))) {
+        error_string = ssl_error_strings[error];
+      } else {
+        error_string = unknown_error_string;
+      }
 
-  err = -err;
+      break;
+
+    default:
+      error_string = unknown_error_string;
+      break;
 
-  if (err < 0 || err > max_error_index) {
-    str = "an unknown error occurred";
-  } else {
-    str = client_error_strings[err];
   }
 
-  return strdup(str);
+  return error_string;
 }
 
 void amqp_abort(const char *fmt, ...)