examples/echo-cpp.cpp

   1 /*
   2  *  A simple FastCGI application example in C++.
   3  *
   4  *  $Id: echo-cpp.cpp,v 1.10 2002/02/25 00:46:17 robs Exp $
   5  *
   6  *  Copyright (c) 2001  Rob Saccoccio and Chelsea Networks
   7  *  All rights reserved.
   8  *
   9  *  Redistribution and use in source and binary forms, with or without
  10  *  modification, are permitted provided that the following conditions
  11  *  are met:
  12  *
  13  *  1. Redistributions of source code must retain the above copyright
  14  *     notice, this list of conditions and the following disclaimer.
  15  *  2. Redistributions in binary form must reproduce the above copyright
  16  *     notice, this list of conditions and the following disclaimer in the
  17  *     documentation and/or other materials provided with the distribution.
  18  *  3. The name of the author may not be used to endorse or promote products
  19  *     derived from this software without specific prior written permission.
  20  *
  21  *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  22  *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  23  *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  24  *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  26  *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  30  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #include <stdlib.h>
  34 #ifdef _WIN32
  35 #include <process.h>
  36 #else
  37 #include <unistd.h>
  38 extern char ** environ;
  39 #endif
  40 #include "fcgio.h"
  41 #include "fcgi_config.h"  // HAVE_IOSTREAM_WITHASSIGN_STREAMBUF
  42
  43 using namespace std;
  44
  45 // Maximum number of bytes allowed to be read from stdin
  46 static const unsigned long STDIN_MAX = 1000000;
  47
  48 static void penv(const char * const * envp)
  49 {
  50     cout << "<PRE>\n";
  51     for ( ; *envp; ++envp)
  52     {
  53         cout << *envp << "\n";
  54     }
  55     cout << "</PRE>\n";
  56 }
  57
  58 static long gstdin(FCGX_Request * request, char ** content)
  59 {
  60     char * clenstr = FCGX_GetParam("CONTENT_LENGTH", request->envp);
  61     unsigned long clen = STDIN_MAX;
  62
  63     if (clenstr)
  64     {
  65         clen = strtol(clenstr, &clenstr, 10);
  66         if (*clenstr)
  67         {
  68             cerr << "can't parse \"CONTENT_LENGTH="
  69                  << FCGX_GetParam("CONTENT_LENGTH", request->envp)
  70                  << "\"\n";
  71             clen = STDIN_MAX;
  72         }
  73
  74         // *always* put a cap on the amount of data that will be read
  75         if (clen > STDIN_MAX) clen = STDIN_MAX;
  76
  77         *content = new char[clen];
  78
  79         cin.read(*content, clen);
  80         clen = cin.gcount();
  81     }
  82     else
  83     {
  84         // *never* read stdin when CONTENT_LENGTH is missing or unparsable
  85         *content = 0;
  86         clen = 0;
  87     }
  88
  89     // Chew up any remaining stdin - this shouldn't be necessary
  90     // but is because mod_fastcgi doesn't handle it correctly.
  91
  92     // ignore() doesn't set the eof bit in some versions of glibc++
  93     // so use gcount() instead of eof()...
  94     do cin.ignore(1024); while (cin.gcount() == 1024);
  95
  96     return clen;
  97 }
  98
  99 int main (void)
 100 {
 101     int count = 0;
 102     long pid = getpid();
 103
 104     streambuf * cin_streambuf  = cin.rdbuf();
 105     streambuf * cout_streambuf = cout.rdbuf();
 106     streambuf * cerr_streambuf = cerr.rdbuf();
 107
 108     FCGX_Request request;
 109
 110     FCGX_Init();
 111     FCGX_InitRequest(&request, 0, 0);
 112
 113     while (FCGX_Accept_r(&request) == 0)
 114     {
 115         // Note that the default bufsize (0) will cause the use of iostream
 116         // methods that require positioning (such as peek(), seek(),
 117         // unget() and putback()) to fail (in favour of more efficient IO).
 118         fcgi_streambuf cin_fcgi_streambuf(request.in);
 119         fcgi_streambuf cout_fcgi_streambuf(request.out);
 120         fcgi_streambuf cerr_fcgi_streambuf(request.err);
 121
 122 #if HAVE_IOSTREAM_WITHASSIGN_STREAMBUF
 123         cin  = &cin_fcgi_streambuf;
 124         cout = &cout_fcgi_streambuf;
 125         cerr = &cerr_fcgi_streambuf;
 126 #else
 127         cin.rdbuf(&cin_fcgi_streambuf);
 128         cout.rdbuf(&cout_fcgi_streambuf);
 129         cerr.rdbuf(&cerr_fcgi_streambuf);
 130 #endif
 131
 132         // Although FastCGI supports writing before reading,
 133         // many http clients (browsers) don't support it (so
 134         // the connection deadlocks until a timeout expires!).
 135         char * content;
 136         unsigned long clen = gstdin(&request, &content);
 137
 138         cout << "Content-type: text/html\r\n"
 139                 "\r\n"
 140                 "<TITLE>echo-cpp</TITLE>\n"
 141                 "<H1>echo-cpp</H1>\n"
 142                 "<H4>PID: " << pid << "</H4>\n"
 143                 "<H4>Request Number: " << ++count << "</H4>\n";
 144
 145         cout << "<H4>Request Environment</H4>\n";
 146         penv(request.envp);
 147
 148         cout << "<H4>Process/Initial Environment</H4>\n";
 149         penv(environ);
 150
 151         cout << "<H4>Standard Input - " << clen;
 152         if (clen == STDIN_MAX) cout << " (STDIN_MAX)";
 153         cout << " bytes</H4>\n";
 154         if (clen) cout.write(content, clen);
 155
 156         if (content) delete []content;
 157
 158         // If the output streambufs had non-zero bufsizes and
 159         // were constructed outside of the accept loop (i.e.
 160         // their destructor won't be called here), they would
 161         // have to be flushed here.
 162     }
 163
 164 #if HAVE_IOSTREAM_WITHASSIGN_STREAMBUF
 165     cin  = cin_streambuf;
 166     cout = cout_streambuf;
 167     cerr = cerr_streambuf;
 168 #else
 169     cin.rdbuf(cin_streambuf);
 170     cout.rdbuf(cout_streambuf);
 171     cerr.rdbuf(cerr_streambuf);
 172 #endif
 173
 174     return 0;
 175 }