sapling/cdatapack/cdatapack_dump.c

// Copyright 2016-present Facebook. All Rights Reserved.
//
// cdatapack_dump.c: Dump the entire contents of a datapack file by walking
//                   the datapack file.
//
// no-check-code

#include <memory.h>
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include "convert.h"
#include "cdatapack.h"

#define DATAIDX_EXT  ".dataidx"
#define DATAPACK_EXT ".datapack"

int main(int argc, char *argv[]) {
  if (argc < 2) {
    fprintf(stderr, "%s <path>\n", argv[0]);
    exit(1);
  }

  long len = strlen(argv[1]);
  char idx_path[len + sizeof(DATAIDX_EXT)];
  char data_path[len + sizeof(DATAPACK_EXT)];

  sprintf(idx_path, "%s%s", argv[1], DATAIDX_EXT);
  sprintf(data_path, "%s%s", argv[1], DATAPACK_EXT);

  datapack_handle_t *handle = open_datapack(
      idx_path, strlen(idx_path),
      data_path, strlen(data_path));

  const uint8_t *ptr = handle->data_mmap;
  const uint8_t *end = ptr + handle->data_file_sz;

  ptr += 1; // for the version field.

  const char *last_filename = NULL;
  uint16_t last_filename_sz = 0;

  char node_buffer[NODE_SZ * 2];
  char deltabase_buffer[NODE_SZ * 2];

  while (ptr < end) {
    delta_chain_link_t link;
    get_delta_chain_link_result_t next;

    next = getdeltachainlink(ptr, &link);
    ptr = next.ptr;

    if (last_filename_sz != link.filename_sz ||
        memcmp(last_filename, link.filename, last_filename_sz) != 0) {
      // print the filename
      printf("\n%-.*s\n", (int) link.filename_sz, link.filename);
      last_filename_sz = link.filename_sz;
      last_filename = link.filename;
    }

    hexlify(link.node, NODE_SZ, node_buffer);
    hexlify(link.deltabase_node, NODE_SZ, deltabase_buffer);

    printf("%-*s  %-*s  %s\n",
        NODE_SZ * 2, "Node", NODE_SZ * 2, "Delta Base",
        "Delta Length");
    printf("%-.*s  %-.*s  %" PRIu64 "\n",
        NODE_SZ * 2, node_buffer, NODE_SZ * 2, deltabase_buffer,
        link.delta_sz);
  }

  close_datapack(handle);
}