Mbed OS 文档翻译 之 参考（API（平台（Debug）））

Debug

Mbed OS 提供了一组调试功能，可用于在运行时将调试消息输出到 STDIO。mbed_debug.h 声明了这些函数，这些函数仅在调试版本中可用。

debug 函数是一个 printf 样式的函数，它接受一个格式字符串后跟参数。 以下是一些示例用法。

void *operator new(std::size_t count) {
    void *buffer = malloc(count);
    if (NULL == buffer) {
        error("Operator new out of memory\r\n");
    } else {
        debug("Operator new succeded");
    }
    return buffer;
}

debug_if 函数类似于调试函数，只是它需要一个额外的参数作为其第一个参数。仅当第一个参数计算结果为 true 时，该消息才会打印到 STDIO。

void *operator new(std::size_t count) {
    debug_if( count == 0, "\nnew called with 0 size");
    ...
}

Debug 函数参考

mbed_debug.h

Debug 示例

main.cpp                                                                                                                                          导入到 Mbed IDE

/* Example usage for Debug, Assert, Error and MemoryStats 
 * Copyright (c) 2016 ARM Limited
 *
 * 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 "mbed.h"
#include "platform/mbed_assert.h"
#include "platform/mbed_debug.h"
#include "platform/mbed_error.h"
#include "platform/mbed_stats.h"

#define MAX_THREAD_INFO 10

mbed_stats_heap_t heap_info;
mbed_stats_stack_t stack_info[ MAX_THREAD_INFO ];
int main()
{
    debug("\nThis message is from debug function");
    debug_if(1,"\nThis message is from debug_if function");
    debug_if(0,"\nSOMETHING WRONG!!! This message from debug_if function shouldn't show on bash");
    
    printf("\nMemoryStats:");
    mbed_stats_heap_get( &heap_info );
    printf("\n\tBytes allocated currently: %d", heap_info.current_size);
    printf("\n\tMax bytes allocated at a given time: %d", heap_info.max_size);
    printf("\n\tCumulative sum of bytes ever allocated: %d", heap_info.total_size);
    printf("\n\tCurrent number of bytes allocated for the heap: %d", heap_info.reserved_size);
    printf("\n\tCurrent number of allocations: %d", heap_info.alloc_cnt);
    printf("\n\tNumber of failed allocations: %d", heap_info.alloc_fail_cnt);
    
    mbed_stats_stack_get( &stack_info[0] );
    printf("\nCumulative Stack Info:");
    printf("\n\tMaximum number of bytes used on the stack: %d", stack_info[0].max_size);
    printf("\n\tCurrent number of bytes allocated for the stack: %d", stack_info[0].reserved_size);
    printf("\n\tNumber of stacks stats accumulated in the structure: %d", stack_info[0].stack_cnt);
    
    mbed_stats_stack_get_each( stack_info, MAX_THREAD_INFO );
    printf("\nThread Stack Info:");
    for(int i=0;i < MAX_THREAD_INFO; i++) {
        if(stack_info[i].thread_id != 0) {
            printf("\n\tThread: %d", i);
            printf("\n\t\tThread Id: 0x%08X", stack_info[i].thread_id);
            printf("\n\t\tMaximum number of bytes used on the stack: %d", stack_info[i].max_size);
            printf("\n\t\tCurrent number of bytes allocated for the stack: %d", stack_info[i].reserved_size);
            printf("\n\t\tNumber of stacks stats accumulated in the structure: %d", stack_info[i].stack_cnt); 
        }        
    }
    
    printf("\nDone...\n\n");
}