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9bada89711
Replace the contents of the tokens GQueue with a simple struct. This cuts the amount of memory allocated by tests/check-qjson from ~500MB to ~20MB, and the execution time from 600ms to 80ms on my laptop. Still a lot (some could be saved by using an intrusive list, such as QSIMPLEQ, instead of the GQueue), but the savings are already massive and the right thing to do would probably be to get rid of json-streamer completely. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1448300659-23559-5-git-send-email-pbonzini@redhat.com> [Straightforwardly rebased on my patches] Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
124 lines
3.2 KiB
C
124 lines
3.2 KiB
C
/*
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* JSON streaming support
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*
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* Copyright IBM, Corp. 2009
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*
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* Authors:
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* Anthony Liguori <aliguori@us.ibm.com>
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*
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* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
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* See the COPYING.LIB file in the top-level directory.
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*
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*/
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#include "qemu-common.h"
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#include "qapi/qmp/json-lexer.h"
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#include "qapi/qmp/json-streamer.h"
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#define MAX_TOKEN_SIZE (64ULL << 20)
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#define MAX_NESTING (1ULL << 10)
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static void json_message_free_tokens(JSONMessageParser *parser)
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{
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if (parser->tokens) {
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g_queue_free(parser->tokens);
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parser->tokens = NULL;
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}
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}
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static void json_message_process_token(JSONLexer *lexer, GString *input,
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JSONTokenType type, int x, int y)
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{
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JSONMessageParser *parser = container_of(lexer, JSONMessageParser, lexer);
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JSONToken *token;
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switch (type) {
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case JSON_LCURLY:
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parser->brace_count++;
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break;
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case JSON_RCURLY:
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parser->brace_count--;
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break;
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case JSON_LSQUARE:
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parser->bracket_count++;
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break;
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case JSON_RSQUARE:
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parser->bracket_count--;
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break;
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default:
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break;
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}
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token = g_malloc(sizeof(JSONToken) + input->len + 1);
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token->type = type;
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memcpy(token->str, input->str, input->len);
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token->str[input->len] = 0;
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token->x = x;
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token->y = y;
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parser->token_size += input->len;
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g_queue_push_tail(parser->tokens, token);
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if (type == JSON_ERROR) {
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goto out_emit_bad;
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} else if (parser->brace_count < 0 ||
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parser->bracket_count < 0 ||
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(parser->brace_count == 0 &&
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parser->bracket_count == 0)) {
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goto out_emit;
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} else if (parser->token_size > MAX_TOKEN_SIZE ||
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parser->bracket_count + parser->brace_count > MAX_NESTING) {
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/* Security consideration, we limit total memory allocated per object
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* and the maximum recursion depth that a message can force.
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*/
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goto out_emit_bad;
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}
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return;
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out_emit_bad:
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/*
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* Clear out token list and tell the parser to emit an error
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* indication by passing it a NULL list
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*/
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json_message_free_tokens(parser);
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out_emit:
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/* send current list of tokens to parser and reset tokenizer */
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parser->brace_count = 0;
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parser->bracket_count = 0;
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/* parser->emit takes ownership of parser->tokens. */
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parser->emit(parser, parser->tokens);
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parser->tokens = g_queue_new();
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parser->token_size = 0;
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}
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void json_message_parser_init(JSONMessageParser *parser,
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void (*func)(JSONMessageParser *, GQueue *))
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{
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parser->emit = func;
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parser->brace_count = 0;
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parser->bracket_count = 0;
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parser->tokens = g_queue_new();
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parser->token_size = 0;
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json_lexer_init(&parser->lexer, json_message_process_token);
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}
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int json_message_parser_feed(JSONMessageParser *parser,
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const char *buffer, size_t size)
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{
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return json_lexer_feed(&parser->lexer, buffer, size);
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}
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int json_message_parser_flush(JSONMessageParser *parser)
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{
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return json_lexer_flush(&parser->lexer);
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}
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void json_message_parser_destroy(JSONMessageParser *parser)
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{
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json_lexer_destroy(&parser->lexer);
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json_message_free_tokens(parser);
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}
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