grpc/test/core/json/json_rewrite.c

/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

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

#include <grpc/support/alloc.h>
#include <grpc/support/cmdline.h>
#include <grpc/support/log.h>

#include "src/core/json/json_reader.h"
#include "src/core/json/json_writer.h"

typedef struct json_writer_userdata
{
  FILE *out;
} json_writer_userdata;

typedef struct stacked_container
{
  grpc_json_type type;
  struct stacked_container *next;
} stacked_container;

typedef struct json_reader_userdata
{
  FILE *in;
  grpc_json_writer *writer;
  char *scratchpad;
  char *ptr;
  size_t free_space;
  size_t allocated;
  size_t string_len;
  stacked_container *top;
} json_reader_userdata;

static void
json_writer_output_char (void *userdata, char c)
{
  json_writer_userdata *state = userdata;
  fputc (c, state->out);
}

static void
json_writer_output_string (void *userdata, const char *str)
{
  json_writer_userdata *state = userdata;
  fputs (str, state->out);
}

static void
json_writer_output_string_with_len (void *userdata, const char *str, size_t len)
{
  json_writer_userdata *state = userdata;
  fwrite (str, len, 1, state->out);
}

grpc_json_writer_vtable writer_vtable = { json_writer_output_char,
  json_writer_output_string,
  json_writer_output_string_with_len
};

static void
check_string (json_reader_userdata * state, size_t needed)
{
  if (state->free_space >= needed)
    return;
  needed -= state->free_space;
  needed = (needed + 0xffu) & ~0xffu;
  state->scratchpad = gpr_realloc (state->scratchpad, state->allocated + needed);
  state->free_space += needed;
  state->allocated += needed;
}

static void
json_reader_string_clear (void *userdata)
{
  json_reader_userdata *state = userdata;
  state->free_space = state->allocated;
  state->string_len = 0;
}

static void
json_reader_string_add_char (void *userdata, gpr_uint32 c)
{
  json_reader_userdata *state = userdata;
  check_string (state, 1);
  GPR_ASSERT (c < 256);
  state->scratchpad[state->string_len++] = (char) c;
}

static void
json_reader_string_add_utf32 (void *userdata, gpr_uint32 c)
{
  if (c <= 0x7f)
    {
      json_reader_string_add_char (userdata, c);
    }
  else if (c <= 0x7ff)
    {
      gpr_uint32 b1 = 0xc0u | ((c >> 6u) & 0x1fu);
      gpr_uint32 b2 = 0x80u | (c & 0x3fu);
      json_reader_string_add_char (userdata, b1);
      json_reader_string_add_char (userdata, b2);
    }
  else if (c <= 0xffffu)
    {
      gpr_uint32 b1 = 0xe0u | ((c >> 12u) & 0x0fu);
      gpr_uint32 b2 = 0x80u | ((c >> 6u) & 0x3fu);
      gpr_uint32 b3 = 0x80u | (c & 0x3fu);
      json_reader_string_add_char (userdata, b1);
      json_reader_string_add_char (userdata, b2);
      json_reader_string_add_char (userdata, b3);
    }
  else if (c <= 0x1fffffu)
    {
      gpr_uint32 b1 = 0xf0u | ((c >> 18u) & 0x07u);
      gpr_uint32 b2 = 0x80u | ((c >> 12u) & 0x3fu);
      gpr_uint32 b3 = 0x80u | ((c >> 6u) & 0x3fu);
      gpr_uint32 b4 = 0x80u | (c & 0x3fu);
      json_reader_string_add_char (userdata, b1);
      json_reader_string_add_char (userdata, b2);
      json_reader_string_add_char (userdata, b3);
      json_reader_string_add_char (userdata, b4);
    }
}

static gpr_uint32
json_reader_read_char (void *userdata)
{
  int r;
  json_reader_userdata *state = userdata;

  r = fgetc (state->in);
  if (r == EOF)
    r = GRPC_JSON_READ_CHAR_EOF;
  return (gpr_uint32) r;
}

static void
json_reader_container_begins (void *userdata, grpc_json_type type)
{
  json_reader_userdata *state = userdata;
  stacked_container *container = gpr_malloc (sizeof (stacked_container));

  container->type = type;
  container->next = state->top;
  state->top = container;

  grpc_json_writer_container_begins (state->writer, type);
}

static grpc_json_type
json_reader_container_ends (void *userdata)
{
  json_reader_userdata *state = userdata;
  stacked_container *container = state->top;

  grpc_json_writer_container_ends (state->writer, container->type);
  state->top = container->next;
  gpr_free (container);
  return state->top ? state->top->type : GRPC_JSON_TOP_LEVEL;
}

static void
json_reader_set_key (void *userdata)
{
  json_reader_userdata *state = userdata;
  json_reader_string_add_char (userdata, 0);

  grpc_json_writer_object_key (state->writer, state->scratchpad);
}

static void
json_reader_set_string (void *userdata)
{
  json_reader_userdata *state = userdata;
  json_reader_string_add_char (userdata, 0);

  grpc_json_writer_value_string (state->writer, state->scratchpad);
}

static int
json_reader_set_number (void *userdata)
{
  json_reader_userdata *state = userdata;

  grpc_json_writer_value_raw_with_len (state->writer, state->scratchpad, state->string_len);

  return 1;
}

static void
json_reader_set_true (void *userdata)
{
  json_reader_userdata *state = userdata;

  grpc_json_writer_value_raw_with_len (state->writer, "true", 4);
}

static void
json_reader_set_false (void *userdata)
{
  json_reader_userdata *state = userdata;

  grpc_json_writer_value_raw_with_len (state->writer, "false", 5);
}

static void
json_reader_set_null (void *userdata)
{
  json_reader_userdata *state = userdata;

  grpc_json_writer_value_raw_with_len (state->writer, "null", 4);
}

static grpc_json_reader_vtable reader_vtable = {
  json_reader_string_clear, json_reader_string_add_char,
  json_reader_string_add_utf32, json_reader_read_char,
  json_reader_container_begins, json_reader_container_ends,
  json_reader_set_key, json_reader_set_string,
  json_reader_set_number, json_reader_set_true,
  json_reader_set_false, json_reader_set_null
};

int
rewrite (FILE * in, FILE * out, int indent)
{
  grpc_json_writer writer;
  grpc_json_reader reader;
  grpc_json_reader_status status;
  json_writer_userdata writer_user;
  json_reader_userdata reader_user;

  reader_user.writer = &writer;
  reader_user.in = in;
  reader_user.top = NULL;
  reader_user.scratchpad = NULL;
  reader_user.string_len = 0;
  reader_user.free_space = 0;
  reader_user.allocated = 0;

  writer_user.out = out;

  grpc_json_writer_init (&writer, indent, &writer_vtable, &writer_user);
  grpc_json_reader_init (&reader, &reader_vtable, &reader_user);

  status = grpc_json_reader_run (&reader);

  free (reader_user.scratchpad);
  while (reader_user.top)
    {
      stacked_container *container = reader_user.top;
      reader_user.top = container->next;
      free (container);
    }

  return status == GRPC_JSON_DONE;
}

int
main (int argc, char **argv)
{
  int indent = 2;
  gpr_cmdline *cl;

  cl = gpr_cmdline_create (NULL);
  gpr_cmdline_add_int (cl, "indent", NULL, &indent);
  gpr_cmdline_parse (cl, argc, argv);
  gpr_cmdline_destroy (cl);

  return rewrite (stdin, stdout, indent) ? 0 : 1;
}