c++ - 如何正确使用 libarchive？

Question

我正在尝试使用 libarchive 压缩/解压缩文件夹。但是，我不知道如何使用它？

Answer 1

包括这些:

#include <archive.h>
#include <archive_entry.h>

并编译:

gcc -Wall -o test test.c -lz -lbz2  -larchive

所以它应该看起来像这样

#include <sys/types.h>

#include <sys/stat.h>

#include <archive.h>
#include <archive_entry.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static int
copy_data(struct archive *ar, struct archive *aw)
{
  int r;
  const void *buff;
  size_t size;
  off_t offset;

  for (;;) {
    r = archive_read_data_block(ar, &buff, &size, &offset);
    if (r == ARCHIVE_EOF)
      return (ARCHIVE_OK);
    if (r < ARCHIVE_OK)
      return (r);
    r = archive_write_data_block(aw, buff, size, offset);
    if (r < ARCHIVE_OK) {
      fprintf(stderr, "%s\n", archive_error_string(aw));
      return (r);
    }
  }
}

static int
extract(const char *filename)
{
  struct archive *a;
  struct archive *ext;
  struct archive_entry *entry;
  int flags;
  int r;

  /* Select which attributes we want to restore. */
  flags = ARCHIVE_EXTRACT_TIME;
  flags |= ARCHIVE_EXTRACT_PERM;
  flags |= ARCHIVE_EXTRACT_ACL;
  flags |= ARCHIVE_EXTRACT_FFLAGS;

  a = archive_read_new();
  archive_read_support_format_all(a);
  ext = archive_write_disk_new();
  archive_write_disk_set_options(ext, flags);
  archive_write_disk_set_standard_lookup(ext);
  if ((r = archive_read_open_filename(a, filename, 10240)))
    return 1;
  for (;;) {
    r = archive_read_next_header(a, &entry);
    if (r == ARCHIVE_EOF)
      break;
    if (r < ARCHIVE_OK)
      fprintf(stderr, "%s\n", archive_error_string(a));
    if (r < ARCHIVE_WARN)
      return 1;
    r = archive_write_header(ext, entry);
    if (r < ARCHIVE_OK)
      fprintf(stderr, "%s\n", archive_error_string(ext));
    else if (archive_entry_size(entry) > 0) {
      r = copy_data(a, ext);
      if (r < ARCHIVE_OK)
        fprintf(stderr, "%s\n", archive_error_string(ext));
      if (r < ARCHIVE_WARN)
        return 1;
    }
    r = archive_write_finish_entry(ext);
    if (r < ARCHIVE_OK)
      fprintf(stderr, "%s\n", archive_error_string(ext));
    if (r < ARCHIVE_WARN)
      return 1;
  }
  archive_read_close(a);
  archive_read_free(a);
  archive_write_close(ext);
  archive_write_free(ext);
  return 0;
}

int main ( int argc, const char **argv )
{
  return extract (argv[1]);;
}