使用C语言设计编写程序日志，实现时间戳、 日志级别、日志内容、 日志输出、 日志轮转功能，同时结合程序日志的配置文件，并给出配置文件的内容，形成.c，.h和测试函数

好的，我可以为您提供一个简单的程序日志实现。首先，我们需要定义日志级别和输出方式：

typedef enum {
    LOG_DEBUG,
    LOG_INFO,
    LOG_WARN,
    LOG_ERROR
} log_level_t;

typedef enum {
    LOG_OUTPUT_CONSOLE,
    LOG_OUTPUT_FILE
} log_output_t;

然后我们定义一个日志结构体，用于存储日志信息：

typedef struct {
    log_level_t level;
    char *message;
    time_t timestamp;
} log_entry_t;

接下来，我们定义一个日志模块，包含初始化、写入日志、切换日志文件等功能：

typedef struct {
    char *filename;
    log_output_t output;
    log_level_t level;
    FILE *file;
    int max_size;
    int max_files;
    int current_file_index;
    log_entry_t *buffer;
    int buffer_size;
    int buffer_count;
} log_module_t;

void log_init(log_module_t *log, char *filename, log_output_t output, log_level_t level, int max_size, int max_files);
void log_write(log_module_t *log, log_level_t level, char *format, ...);
void log_switch_file(log_module_t *log);
void log_cleanup(log_module_t *log);

在初始化函数中，我们需要读取配置文件，配置文件的格式如下：

[log]
filename=log.txt
output=console
level=info
max_size=10240
max_files=5

我们可以使用`ini`库来解析配置文件。具体实现可以参考以下代码：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <time.h>
#include "ini.h"

#define LOG_MAX_BUFFER_SIZE 1024
#define LOG_MAX_FILE_NAME 256
#define LOG_MAX_TIMESTAMP_SIZE 32

static char log_level_names[][6] = {"DEBUG", "INFO", "WARN", "ERROR"};

static void log_write_to_file(log_module_t *log, log_entry_t *entry);
static void log_write_to_console(log_entry_t *entry);
static void log_rotate_files(log_module_t *log);

static int log_config_handler(void *user, const char *section, const char *name, const char *value) {
    log_module_t *log = (log_module_t*) user;

    if (strcasecmp(section, "log") == 0) {
        if (strcasecmp(name, "filename") == 0) {
            log->filename = strdup(value);
        } else if (strcasecmp(name, "output") == 0) {
            if (strcasecmp(value, "console") == 0) {
                log->output = LOG_OUTPUT_CONSOLE;
            } else if (strcasecmp(value, "file") == 0) {
                log->output = LOG_OUTPUT_FILE;
            }
        } else if (strcasecmp(name, "level") == 0) {
            if (strcasecmp(value, "debug") == 0) {
                log->level = LOG_DEBUG;
            } else if (strcasecmp(value, "info") == 0) {
                log->level = LOG_INFO;
            } else if (strcasecmp(value, "warn") == 0) {
                log->level = LOG_WARN;
            } else if (strcasecmp(value, "error") == 0) {
                log->level = LOG_ERROR;
            }
        } else if (strcasecmp(name, "max_size") == 0) {
            log->max_size = atoi(value);
        } else if (strcasecmp(name, "max_files") == 0) {
            log->max_files = atoi(value);
        }
    }

    return 1;
}

void log_init(log_module_t *log, char *filename, log_output_t output, log_level_t level, int max_size, int max_files) {
    log->filename = filename;
    log->output = output;
    log->level = level;
    log->max_size = max_size;
    log->max_files = max_files;
    log->file = NULL;
    log->buffer = (log_entry_t*) calloc(log->max_size, sizeof(log_entry_t));
    log->buffer_size = log->max_size;
    log->buffer_count = 0;
    log->current_file_index = 0;

    ini_parse("log.ini", log_config_handler, log);
}

void log_write(log_module_t *log, log_level_t level, char *format, ...) {
    if (level < log->level) {
        return;
    }

    log_entry_t entry;
    entry.level = level;
    entry.message = (char*) malloc(LOG_MAX_BUFFER_SIZE);
    entry.timestamp = time(NULL);

    va_list args;
    va_start(args, format);
    vsnprintf(entry.message, LOG_MAX_BUFFER_SIZE, format, args);
    va_end(args);

    if (log->output == LOG_OUTPUT_FILE) {
        log_write_to_file(log, &entry);
    } else {
        log_write_to_console(&entry);
    }

    free(entry.message);
}

void log_switch_file(log_module_t *log) {
    if (log->output != LOG_OUTPUT_FILE) {
        return;
    }

    fclose(log->file);

    char filename[LOG_MAX_FILE_NAME];
    snprintf(filename, LOG_MAX_FILE_NAME, "%s.%d", log->filename, log->current_file_index);

    rename(log->filename, filename);

    log->file = fopen(log->filename, "a+");
    if (log->file == NULL) {
        log->file = fopen(log->filename, "w");
    }

    log_rotate_files(log);
}

void log_cleanup(log_module_t *log) {
    if (log->output == LOG_OUTPUT_FILE) {
        fclose(log->file);
    }

    free(log->filename);
    free(log->buffer);
}

static void log_write_to_file(log_module_t *log, log_entry_t *entry) {
    if (log->buffer_count >= log->buffer_size) {
        log_rotate_files(log);
    }

    fwrite(entry->message, strlen(entry->message), 1, log->file);
    fflush(log->file);

    log->buffer[log->buffer_count++] = *entry;
}

static void log_write_to_console(log_entry_t *entry) {
    char timestamp[LOG_MAX_TIMESTAMP_SIZE];
    strftime(timestamp, LOG_MAX_TIMESTAMP_SIZE, "%Y-%m-%d %H:%M:%S", localtime(&entry->timestamp));

    printf("[%s] %s: %s\n", timestamp, log_level_names[entry->level], entry->message);
}

static void log_rotate_files(log_module_t *log) {
    if (log->max_files <= 1) {
        return;
    }

    char filename[LOG_MAX_FILE_NAME];

    for (int i = log->max_files - 2; i >= 0; i--) {
        if (i == 0) {
            snprintf(filename, LOG_MAX_FILE_NAME, "%s", log->filename);
        } else {
            snprintf(filename, LOG_MAX_FILE_NAME, "%s.%d", log->filename, i);
        }

        char new_filename[LOG_MAX_FILE_NAME];
        snprintf(new_filename, LOG_MAX_FILE_NAME, "%s.%d", log->filename, i + 1);

        rename(filename, new_filename);
    }

    log->current_file_index++;
    if (log->current_file_index >= log->max_files) {
        log->current_file_index = 0;
    }

    char new_filename[LOG_MAX_FILE_NAME];
    snprintf(new_filename, LOG_MAX_FILE_NAME, "%s.%d", log->filename, log->current_file_index);

    fclose(log->file);
    log->file = fopen(new_filename, "a+");
    if (log->file == NULL) {
        log->file = fopen(new_filename, "w");
    }

    log->buffer_count = 0;
}

最后，我们可以编写一个测试函数来测试程序日志的功能：

void test_log() {
    log_module_t log;
    log_init(&log, "log.txt", LOG_OUTPUT_CONSOLE, LOG_DEBUG, 10240, 5);

    log_write(&log, LOG_DEBUG, "This is a debug message.");
    log_write(&log, LOG_INFO, "This is an info message.");
    log_write(&log, LOG_WARN, "This is a warning message.");
    log_write(&log, LOG_ERROR, "This is an error message.");

    for (int i = 0; i < 10000; i++) {
        log_write(&log, LOG_INFO, "This is message #%d.", i);
    }

    log_cleanup(&log);
}

以上代码实现了一个简单的程序日志，包含时间戳、日志级别、日志内容、日志输出、日志轮转等功能。