将串口打印的日志，同时备份到sd卡里

将串口打印的日志同时备份到sd卡里#include stdio.h #include unistd.h #include pthread.h #include string.h #include stdlib.h #include errno.h static int pipe_fd[2] {-1, -1}; static int stdout_backup -1; static int stderr_backup -1; static FILE *log_fp NULL; static pthread_t log_tid; static int log_running 0; void strip_ansi_and_write(FILE *fp, const char *buf, int len) { char clean[1024]; int j 0; for (int i 0; i len; i) { // ANSI 转义开始 if (buf[i] 0x1B buf[i 1] [) { i 2; // 跳过直到字母结束 while (i len ((buf[i] 0 buf[i] 9) || buf[i] ;)) { i; } continue; } clean[j] buf[i]; if (j sizeof(clean) - 1) break; } fwrite(clean, 1, j, fp); } void *log_thread(void *arg) { char buf[512]; int n; while (log_running) { n read(pipe_fd[0], buf, sizeof(buf)); if (n 0) { break; } // 输出到原串口 if (stdout_backup 0) { write(stdout_backup, buf, n); } // 写文件 if (log_fp) { strip_ansi_and_write(log_fp, buf, n); } } return NULL; } void log_redirect_init() { if (log_running) return; if (pipe(pipe_fd) 0) { perror(pipe); return; } stdout_backup dup(STDOUT_FILENO); stderr_backup dup(STDERR_FILENO); log_fp fopen(/mnt/sdcard/ipc_dev.txt, a); if (!log_fp) { perror(open log file failed); } // 缓冲区大小 5KB setvbuf(log_fp, NULL, _IOFBF, 5*1024); dup2(pipe_fd[1], STDOUT_FILENO); dup2(pipe_fd[1], STDERR_FILENO); log_running 1; pthread_create(log_tid, NULL, log_thread, NULL); } void log_redirect_deinit() { if (!log_running) return; printf(log_redirect_deinit\n); log_running 0; // 恢复 stdout/stderr if (stdout_backup 0) { dup2(stdout_backup, STDOUT_FILENO); close(stdout_backup); stdout_backup -1; } if (stderr_backup 0) { dup2(stderr_backup, STDERR_FILENO); close(stderr_backup); stderr_backup -1; } // 关闭 pipe if (pipe_fd[0] 0) { close(pipe_fd[0]); pipe_fd[0] -1; } if (pipe_fd[1] 0) { close(pipe_fd[1]); pipe_fd[1] -1; } // 等待线程退出 pthread_join(log_tid, NULL); // 关闭文件 if (log_fp) { fflush(log_fp); fclose(log_fp); log_fp NULL; } printf(log redirect stopped\n); } //// 调用示例 if (sdcard_mounted) { // sd卡插上将日志备份到 sd卡上 log_redirect_init(); } if (sdcard_removed) { // sd卡拔出终止将日志备份到 sd卡上 log_redirect_deinit(); }