用c调用lzma压缩文件

要在C语言中调用 LZMA 压缩文件，需要使用 LZMA SDK 提供的函数和结构体。以下是一个基本的示例：

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <lzma.h>

#define BUF_SIZE 1024

int main(int argc, char *argv[])
{
    if (argc != 3) {
        fprintf(stderr, "Usage: %s <source_file> <dest_file>\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    FILE *src_file = fopen(argv[1], "rb");
    if (!src_file) {
        fprintf(stderr, "Failed to open source file: %s\n", strerror(errno));
        exit(EXIT_FAILURE);
    }

    FILE *dst_file = fopen(argv[2], "wb");
    if (!dst_file) {
        fprintf(stderr, "Failed to open destination file: %s\n", strerror(errno));
        fclose(src_file);
        exit(EXIT_FAILURE);
    }

    lzma_stream strm = LZMA_STREAM_INIT;
    lzma_ret ret = lzma_easy_encoder(&strm, 6, LZMA_CHECK_CRC64);
    if (ret != LZMA_OK) {
        fprintf(stderr, "Failed to initialize LZMA encoder: %s\n", lzma_strerror(ret));
        fclose(dst_file);
        fclose(src_file);
        exit(EXIT_FAILURE);
    }

    uint8_t in_buf[BUF_SIZE];
    uint8_t out_buf[BUF_SIZE];

    strm.next_out = out_buf;
    strm.avail_out = sizeof(out_buf);

    do {
        strm.next_in = in_buf;
        strm.avail_in = fread(in_buf, 1, sizeof(in_buf), src_file);
        if (ferror(src_file)) {
            fprintf(stderr, "Failed to read source file: %s\n", strerror(errno));
            lzma_end(&strm);
            fclose(dst_file);
            fclose(src_file);
            exit(EXIT_FAILURE);
        }

        ret = lzma_code(&strm, LZMA_RUN);
        if (ret != LZMA_OK && ret != LZMA_STREAM_END) {
            fprintf(stderr, "Failed to compress data: %s\n", lzma_strerror(ret));
            lzma_end(&strm);
            fclose(dst_file);
            fclose(src_file);
            exit(EXIT_FAILURE);
        }

        size_t out_size = sizeof(out_buf) - strm.avail_out;
        if (fwrite(out_buf, 1, out_size, dst_file) != out_size) {
            fprintf(stderr, "Failed to write compressed data: %s\n", strerror(errno));
            lzma_end(&strm);
            fclose(dst_file);
            fclose(src_file);
            exit(EXIT_FAILURE);
        }

        strm.next_out = out_buf;
        strm.avail_out = sizeof(out_buf);

    } while (strm.avail_in > 0);

    ret = lzma_code(&strm, LZMA_FINISH);
    if (ret != LZMA_OK && ret != LZMA_STREAM_END) {
        fprintf(stderr, "Failed to finish compression: %s\n", lzma_strerror(ret));
        lzma_end(&strm);
        fclose(dst_file);
        fclose(src_file);
        exit(EXIT_FAILURE);
    }

    size_t out_size = sizeof(out_buf) - strm.avail_out;
    if (fwrite(out_buf, 1, out_size, dst_file) != out_size) {
        fprintf(stderr, "Failed to write compressed data: %s\n", strerror(errno));
        lzma_end(&strm);
        fclose(dst_file);
        fclose(src_file);
        exit(EXIT_FAILURE);
    }

    lzma_end(&strm);
    fclose(dst_file);
    fclose(src_file);

    return 0;
}

这个程序会将源文件压缩为 LZMA 格式，并保存到目标文件中。在程序中，使用 `lzma_easy_encoder` 函数初始化 LZMA 编码器，使用 `lzma_code` 函数进行压缩，最后使用 `lzma_end` 函数关闭编码器。需要注意的是，LZMA SDK 提供了多种压缩选项，例如压缩级别和校验方式，在这个示例中使用的是较为常见的选项。