Merge pull request #8076 from kjbracey-arm/error_stderr

Error output improvements

Author: Cruz Monrreal

drivers/UARTSerial.cpp

@@ -134,6 +134,23 @@ void UARTSerial::sigio(Callback<void()> func)
     core_util_critical_section_exit();
 }
 
+/* Special synchronous write designed to work from critical section, such
+ * as in mbed_error_vprintf.
+ */
+ssize_t UARTSerial::write_unbuffered(const char *buf_ptr, size_t length)
+{
+    while (!_txbuf.empty()) {
+        tx_irq();
+    }
+
+    for (size_t data_written = 0; data_written < length; data_written++) {
+        SerialBase::_base_putc(*buf_ptr++);
+        data_written++;
+    }
+
+    return length;
+}
+
 ssize_t UARTSerial::write(const void *buffer, size_t length)
 {
     size_t data_written = 0;
@@ -143,6 +160,10 @@ ssize_t UARTSerial::write(const void *buffer, size_t length)
         return 0;
     }
 
+    if (core_util_in_critical_section()) {
+        return write_unbuffered(buf_ptr, length);
+    }
+
     api_lock();
 
     // Unlike read, we should write the whole thing if blocking. POSIX only

drivers/UARTSerial.h

@@ -238,6 +238,9 @@ class UARTSerial : private SerialBase, public FileHandle, private NonCopyable<UA
     /** Release mutex */
     virtual void api_unlock(void);
 
+    /** Unbuffered write - invoked when write called from critical section */
+    ssize_t write_unbuffered(const char *buf_ptr, size_t length);
+
     /** Software serial buffers
      *  By default buffer size is 256 for TX and 256 for RX. Configurable through mbed_app.json
      */

platform/mbed_board.c

@@ -18,13 +18,8 @@
 #include "platform/mbed_wait_api.h"
 #include "platform/mbed_toolchain.h"
 #include "platform/mbed_interface.h"
+#include "platform/mbed_retarget.h"
 #include "platform/mbed_critical.h"
-#include "hal/serial_api.h"
-
-#if DEVICE_SERIAL
-extern int stdio_uart_inited;
-extern serial_t stdio_uart;
-#endif
 
 WEAK void mbed_die(void)
 {
@@ -55,36 +50,41 @@ void mbed_error_printf(const char *format, ...)
 {
     va_list arg;
     va_start(arg, format);
-    mbed_error_vfprintf(format, arg);
+    mbed_error_vprintf(format, arg);
     va_end(arg);
 }
 
-void mbed_error_vfprintf(const char *format, va_list arg)
+void mbed_error_vprintf(const char *format, va_list arg)
 {
-#if DEVICE_SERIAL
-#define ERROR_BUF_SIZE      (128)
     core_util_critical_section_enter();
-    char buffer[ERROR_BUF_SIZE];
-    int size = vsnprintf(buffer, ERROR_BUF_SIZE, format, arg);
-    if (size > 0) {
-        if (!stdio_uart_inited) {
-            serial_init(&stdio_uart, STDIO_UART_TX, STDIO_UART_RX);
-        }
-#if MBED_CONF_PLATFORM_STDIO_CONVERT_NEWLINES
-        char stdio_out_prev = '\0';
-        for (int i = 0; i < size; i++) {
-            if (buffer[i] == '\n' && stdio_out_prev != '\r') {
-                serial_putc(&stdio_uart, '\r');
-            }
-            serial_putc(&stdio_uart, buffer[i]);
-            stdio_out_prev = buffer[i];
+    char buffer[132];
+    int size = vsnprintf(buffer, sizeof buffer, format, arg);
+    if (size >= sizeof buffer) {
+        /* Output was truncated - indicate by overwriting last 4 bytes of buffer
+         * with ellipsis and newline.
+         * (Note that although vsnprintf always leaves a NUL terminator, we
+         * don't need a terminator and can use the entire buffer)
+         */
+        memcpy(&buffer[sizeof buffer - 4], "...\n", 4);
+        size = sizeof buffer;
+    }
+#if MBED_CONF_PLATFORM_STDIO_CONVERT_NEWLINES || MBED_CONF_PLATFORM_STDIO_CONVERT_TTY_NEWLINES
+    char stdio_out_prev = '\0';
+    for (int i = 0; i < size; i++) {
+        if (buffer[i] == '\n' && stdio_out_prev != '\r') {
+            const char cr = '\r';
+            write(STDERR_FILENO, &cr, 1);
         }
+        write(STDERR_FILENO, &buffer[i], 1);
+        stdio_out_prev = buffer[i];
+    }
 #else
-        for (int i = 0; i < size; i++) {
-            serial_putc(&stdio_uart, buffer[i]);
-        }
+    write(STDERR_FILENO, buffer, size);
 #endif
-    }
     core_util_critical_section_exit();
-#endif
+}
+
+void mbed_error_vfprintf(const char *format, va_list arg)
+{
+    mbed_error_vprintf(format, arg);
 }

platform/mbed_error.c

@@ -89,7 +89,7 @@ WEAK void error(const char *format, ...)
 #ifndef NDEBUG
     va_list arg;
     va_start(arg, format);
-    mbed_error_vfprintf(format, arg);
+    mbed_error_vprintf(format, arg);
     va_end(arg);
 #endif
     exit(1);

platform/mbed_error.h

@@ -42,7 +42,7 @@ extern "C" {
 #else //MBED_CONF_PLATFORM_MAX_ERROR_FILENAME_LEN
 #if MBED_CONF_PLATFORM_MAX_ERROR_FILENAME_LEN > 64
 //We have to limit this to 64 bytes since we use mbed_error_printf for error reporting
-//and mbed_error_vfprintf uses 128bytes internal buffer which may not be sufficient for anything
+//and mbed_error_vprintf uses 128bytes internal buffer which may not be sufficient for anything
 //longer that 64 bytes with the current implementation.
 #error "Unsupported error filename buffer length detected, max supported length is 64 chars. Please change MBED_CONF_PLATFORM_MAX_ERROR_FILENAME_LEN or max-error-filename-len in configuration."
 #endif

platform/mbed_interface.h

@@ -26,6 +26,7 @@
 
 #include <stdarg.h>
 
+#include "mbed_toolchain.h"
 #include "device.h"
 
 /* Mbed interface mac address
@@ -146,9 +147,15 @@ void mbed_error_printf(const char *format, ...);
  * @param arg       Variable arguments list
  *
  */
+void mbed_error_vprintf(const char *format, va_list arg);
+
+/** @deprecated   Renamed to mbed_error_vprintf to match functionality */
+MBED_DEPRECATED_SINCE("mbed-os-5.11",
+                          "Renamed to mbed_error_vprintf to match functionality.")
 void mbed_error_vfprintf(const char *format, va_list arg);
 /** @}*/
 
+
 #ifdef __cplusplus
 }
 #endif

platform/mbed_retarget.cpp

@@ -1250,6 +1250,8 @@ extern "C" void exit(int return_code)
 #if MBED_CONF_PLATFORM_STDIO_FLUSH_AT_EXIT
     fflush(stdout);
     fflush(stderr);
+    fsync(STDOUT_FILENO);
+    fsync(STDERR_FILENO);
 #endif
 #endif
 

rtos/TARGET_CORTEX/TARGET_CORTEX_M/mbed_rtx_fault_handler.c

@@ -18,7 +18,6 @@
 #include "device.h"
 #include "platform/mbed_error.h"
 #include "platform/mbed_interface.h"
-#include "hal/serial_api.h"
 
 #ifndef MBED_FAULT_HANDLER_DISABLED
 #include "mbed_rtx_fault_handler.h"