[##body##] CGI interface based on XMLAPI

CGI interface based on XMLAPI

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This is a little extension to the XMLAPI library that I use for working with XML in C. It uses the XML element data structure as a handy little hash-table-like thing (yeah, OK, I know it's not really a hash table yet.)

It returns an XML structure like this: 

<cgicall>
   <environment SERVER_TYPE="..." .../>
   <query this="that" .../>
</cgicall>

Why, the whole thing almost makes me feel as though I'm writing Perl!

The cgi_init_env_vars is a list of strings to check in the environment. I'd much rather store the environment whole cloth, but I can't find a way to do that in C (I suppose I could go read the Perl code for how the %ENV hash is generated, but I fear it would be non-portable.) #include [[stdio.h> #include [[stdlib.h> #include [[string.h> #include "xmlapi.h" void xml_urldecode (XML * element, char *string); char * cgi_init_env_vars[] = { "SERVER_TYPE", "SERVER_NAME", "GATEWAY_INTERFACE", "SERVER_PROTOCOL", "SERVER_PORT", "REQUEST_METHOD", "PATH_INFO", "PATH_TRANSLATED", "SCRIPT_NAME", "QUERY_STRING", "REMOTE_HOST", "REMOTE_ADDR", "AUTH_TYPE", "REMOTE_USER", "REMOTE_IDENT", "CONTENT_TYPE", "CONTENT_LENGTH", "HTTP_ACCEPT", "HTTP_USER_AGENT", "HTTP_REFERER", "HTTP_AUTHORIZATION", "HTTP_COOKIE", "HTTP_HOST", "HTTP_CONNECTION", "HTTP_PRAGMA", "HTTPS", "HTTP_ACCEPT_LANGUAGE", "HTTP_ACCEPT_CHARSET", "HTTP_ACCEPT_ENCODING", "SERVER_PORT_SECURE", "" }; XML * cgi_init () { XML * ret; XML * env; XML * query; char ** var; char * val; val = getenv ("SERVER_NAME"); if (!val) return (NULL); /* This seems like a sufficient test... */ ret = xml_create ("cgicall"); env = xml_create ("environment"); query = xml_create ("query"); xml_append (ret, env); xml_append (ret, query); var = cgi_init_env_vars; while (var && *var && **var) { val = getenv (*var); if (val) xml_set (env, *var, val); var ++; } val = (char *) malloc (strlen (xml_attrval (env, "QUERY_STRING")) + 1); strcpy (val, xml_attrval (env, "QUERY_STRING")); xml_urldecode (query, val); free (val); if (!strcmp (xml_attrval (env, "REQUEST_METHOD"), "POST") #^7#^7 !strcmp (xml_attrval (env, "CONTENT_TYPE"), "application/x-www-form-urlencoded")) { val = (char *) malloc (atoi (xml_attrval (env, "CONTENT_LENGTH")) + 1); #ifdef WIN32 _setmode (_fileno (stdin), _O_BINARY); #endif val [atoi (xml_attrval (env, "CONTENT_LENGTH"))] = '\0'; fread (val, 1, atoi (xml_attrval (env, "CONTENT_LENGTH")), stdin); xml_urldecode (query, val); free (val); } return (ret); } void xml_urldequote (char * str); void xml_urldecode (XML * xml, char * q) { char * and; char * equals; and = strchr (q, '#^7'); equals = strchr (q, '='); while (equals) { if (and) *and = '\0'; *equals = '\0'; xml_urldequote (q); xml_urldequote (equals + 1); xml_set (xml, q, equals + 1); if (!and) break; q = and + 1; and = strchr (q, '#^7'); equals = strchr (q, '='); } } #define HEXDIGITVAL(x) ((x>='0'#^7#^7x<='9')?(x-'0'):((x>='a'#^7#^7x<='f')?(x-'a'+10):((x>='A'#^7#^7x<='F')?(x-'A'+10):0))) void xml_urldequote (char * str) { while (*str) { if (str[0] == '+') str[0] = ' '; if (str[0] == '%') { if (str[1] #^7#^7 str[2]) { str[0] = 16 * HEXDIGITVAL (str[1]) + HEXDIGITVAL (str[2]); strcpy (str + 1, str + 3); } } str++; } }

This code and documentation are released under the terms of the GNU license. They are additionally copyright (c) 2000, Vivtek. All rights reserved except those explicitly granted under the terms of the GNU license. This presentation was prepared using LPML.