core: Add wcore_error module

This adds the following functions:
    wcore_error
    wcore_errorf
    wcore_error_get_code
    wcore_error_get_message

Signed-off-by: Chad Versace <chad.versace@linux.intel.com>

2 files changed, 171 insertions, 0 deletions

diff --git a/src/waffle/core/wcore_error.c b/src/waffle/core/wcore_error.c
new file mode 100644
index 0000000..7d39f0a
--- /dev/null
+++ b/src/waffle/core/wcore_error.c
@@ -0,0 +1,110 @@
+// Copyright 2012 Intel Corporation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "wcore_error.h"
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+enum {
+    MESSAGE_MAX = 1023,
+};
+
+static bool wcore_error_is_enabled = true;
+static int wcore_error_code = WAFFLE_NO_ERROR;
+static char wcore_error_message[MESSAGE_MAX + 1]; // +1 for null
+
+void
+_wcore_error_enable(void)
+{
+    wcore_error_is_enabled = true;
+}
+
+void
+_wcore_error_disable(void)
+{
+    wcore_error_is_enabled = false;
+}
+
+void
+wcore_error(int error)
+{
+    if (!wcore_error_is_enabled)
+        return;
+
+    wcore_error_code = error;
+    wcore_error_message[0] = '\0';
+}
+
+void
+wcore_errorf(int error, const char *format, ...)
+{
+    va_list ap;
+
+    if (!wcore_error_is_enabled)
+        return;
+
+    wcore_error_code = error;
+    va_start(ap, format);
+    vsnprintf(wcore_error_message, MESSAGE_MAX, format, ap);
+    va_end(ap);
+}
+
+void
+_wcore_error_internal(const char *file, int line, const char *format, ...)
+{
+    char *cur = wcore_error_message;
+    char *end = wcore_error_message + sizeof(wcore_error_message);
+    int printed;
+
+    if (!wcore_error_is_enabled)
+        return;
+
+    wcore_error_code = WAFFLE_INTERNAL_ERROR;
+
+    printed = snprintf(cur, end - cur,
+                       "waffle: internal error: %s:%d: ", file, line);
+    cur += printed;
+
+    if (printed < 0  || cur >= end)
+        return;
+
+    if (format) {
+        va_list ap;
+
+        va_start(ap, format);
+        printed = vsnprintf(cur, end - cur, format, ap);
+        cur += printed;
+        va_end(ap);
+
+        if (printed < 0 || cur >= end)
+            return;
+    }
+
+    snprintf(cur, end - cur, " (report this bug to chad@chad-versace.us)");
+}
+
+int
+wcore_error_get_code(void)
+{
+    return wcore_error_code;
+}
+
+const char*
+wcore_error_get_message(void)
+{
+    return wcore_error_message;
+}
\ No newline at end of file
diff --git a/src/waffle/core/wcore_error.h b/src/waffle/core/wcore_error.h
new file mode 100644
index 0000000..3457842
--- /dev/null
+++ b/src/waffle/core/wcore_error.h
@@ -0,0 +1,61 @@
+// Copyright 2012 Intel Corporation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include <waffle/waffle_error.h>
+
+/// @brief Set error code for client.
+///
+/// @param error is an `enum waffle_error`.
+void
+wcore_error(int error);
+
+/// @brief Set error code and message for client.
+///
+/// @param error is an `enum waffle_error`.
+/// @param format may be null.
+void
+wcore_errorf(int error, const char *format, ...);
+
+/// @brief Set error to WAFFLE_INTERNAL_ERROR with source location.
+#define wcore_error_internal(format, ...) \
+    _wcore_error_internal(__FILE__, __LINE__, format, __VA_ARGS__)
+
+/// @brief Execute a statement with errors disabled.
+#define WCORE_ERROR_DISABLED(statement) \
+    do { \
+        _wcore_error_disable(); \
+        statement \
+        _wcore_error_enable(); \
+    } while (0)
+
+/// @brief Get the last set error code.
+int
+wcore_error_get_code(void);
+
+/// @brief Get the last set error message.
+const char*
+wcore_error_get_message(void);
+
+/// @defgroup wcore_error private
+/// @{
+
+void
+_wcore_error_internal(const char *file, int line, const char *format, ...);
+
+void _wcore_error_enable(void);
+void _wcore_error_disable(void);
+
+/// @}
\ No newline at end of file