diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/examples/.gitignore | 2 | ||||
| -rw-r--r-- | docs/examples/README | 1 | ||||
| -rw-r--r-- | docs/examples/xmlstream.c | 158 |
3 files changed, 161 insertions, 0 deletions
diff --git a/docs/examples/.gitignore b/docs/examples/.gitignore index cbe0d04d4..40bd837b8 100644 --- a/docs/examples/.gitignore +++ b/docs/examples/.gitignore @@ -43,3 +43,5 @@ simplessl smtp-multi smtp-tls url2file +usercertinmem +xmlstream diff --git a/docs/examples/README b/docs/examples/README index b89338f62..1ca62a154 100644 --- a/docs/examples/README +++ b/docs/examples/README @@ -78,4 +78,5 @@ simplepost.c - HTTP POST simplessl.c - HTTPS example with certificates many options set synctime.c - Sync local time by extracting date from remote HTTP servers url2file.c - download a document and store it in a file +xmlstream.c - Stream-parse a document using the streaming Expat parser 10-at-a-time.c - Download many files simultaneously, 10 at a time. diff --git a/docs/examples/xmlstream.c b/docs/examples/xmlstream.c new file mode 100644 index 000000000..4d67f98eb --- /dev/null +++ b/docs/examples/xmlstream.c @@ -0,0 +1,158 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at http://curl.haxx.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ***************************************************************************/ +/* Stream-parse a document using the streaming Expat parser. + * Written by David Strauss + * + * Expat => http://www.libexpat.org/ + * + * gcc -Wall -I/usr/local/include xmlstream.c -lcurl -lexpat -o xmlstream + * + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> + +#include <expat.h> +#include <curl/curl.h> + +struct MemoryStruct { + char *memory; + size_t size; +}; + +struct ParserStruct { + int ok; + size_t tags; + size_t depth; + struct MemoryStruct characters; +}; + +static void startElement(void *userData, const XML_Char *name, const XML_Char **atts) +{ + struct ParserStruct *state = (struct ParserStruct *) userData; + state->tags++; + state->depth++; + + /* Get a clean slate for reading in character data. */ + free(state->characters.memory); + state->characters.memory = NULL; + state->characters.size = 0; +} + +static void characterDataHandler(void *userData, const XML_Char *s, int len) +{ + struct ParserStruct *state = (struct ParserStruct *) userData; + struct MemoryStruct *mem = &state->characters; + + mem->memory = realloc(mem->memory, mem->size + len + 1); + if(mem->memory == NULL) { + /* Out of memory. */ + fprintf(stderr, "Not enough memory (realloc returned NULL).\n"); + state->ok = 0; + return; + } + + memcpy(&(mem->memory[mem->size]), s, len); + mem->size += len; + mem->memory[mem->size] = 0; +} + +static void endElement(void *userData, const XML_Char *name) +{ + struct ParserStruct *state = (struct ParserStruct *) userData; + state->depth--; + + printf("%5lu %10lu %s\n", state->depth, state->characters.size, name); +} + +static size_t parseStreamCallback(void *contents, size_t length, size_t nmemb, void *userp) +{ + XML_Parser parser = (XML_Parser) userp; + size_t real_size = length * nmemb; + struct ParserStruct *state = (struct ParserStruct *) XML_GetUserData(parser); + + /* Only parse if we're not already in a failure state. */ + if (state->ok && XML_Parse(parser, contents, real_size, 0) == 0) { + int error_code = XML_GetErrorCode(parser); + fprintf(stderr, "Parsing response buffer of length %lu failed with error code %d (%s).\n", + real_size, error_code, XML_ErrorString(error_code)); + state->ok = 0; + } + + return real_size; +} + +int main(void) +{ + CURL *curl_handle; + CURLcode res; + XML_Parser parser; + struct ParserStruct state; + + /* Initialize the state structure for parsing. */ + memset(&state, 0, sizeof(struct ParserStruct)); + state.ok = 1; + + /* Initialize a namespace-aware parser. */ + parser = XML_ParserCreateNS(NULL, '\0'); + XML_SetUserData(parser, &state); + XML_SetElementHandler(parser, startElement, endElement); + XML_SetCharacterDataHandler(parser, characterDataHandler); + + /* Initalize a libcurl handle. */ + curl_global_init(CURL_GLOBAL_ALL ^ CURL_GLOBAL_SSL); + curl_handle = curl_easy_init(); + curl_easy_setopt(curl_handle, CURLOPT_URL, "http://www.w3schools.com/xml/simple.xml"); + curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, parseStreamCallback); + curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, (void *)parser); + + printf("Depth Characters Closing Tag\n"); + + /* Perform the request and any follow-up parsing. */ + res = curl_easy_perform(curl_handle); + if(res != CURLE_OK) { + fprintf(stderr, "curl_easy_perform() failed: %s\n", + curl_easy_strerror(res)); + } + else if (state.ok) { + /* Expat requires one final call to finalize parsing. */ + if (XML_Parse(parser, NULL, 0, 1) == 0) { + int error_code = XML_GetErrorCode(parser); + fprintf(stderr, "Finalizing parsing failed with error code %d (%s).\n", + error_code, XML_ErrorString(error_code)); + } + else { + printf(" --------------\n"); + printf(" %lu tags total\n", state.tags); + } + } + + /* Clean up. */ + free(state.characters.memory); + XML_ParserFree(parser); + curl_easy_cleanup(curl_handle); + curl_global_cleanup(); + + return 0; +} |