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[fcgi2.git] / examples / echo-cpp.cpp
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1 /*
2 * A simple FastCGI application example in C++.
3 *
4 * $Id: echo-cpp.cpp,v 1.4 2001/11/21 20:18:46 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:
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.
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.
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"
42 // Maximum number of bytes allowed to be read from stdin
43 static const unsigned long STDIN_MAX = 1000000;
45 static void penv(const char * const * envp)
47 cout << "<PRE>\n";
48 for ( ; *envp; ++envp)
50 cout << *envp << "\n";
52 cout << "</PRE>\n";
55 static long gstdin(FCGX_Request * request, char ** content)
57 char * clenstr = FCGX_GetParam("CONTENT_LENGTH", request->envp);
58 unsigned long clen = STDIN_MAX;
60 if (clenstr)
62 clen = strtol(clenstr, &clenstr, 10);
63 if (*clenstr)
65 cerr << "can't parse \"CONTENT_LENGTH="
66 << FCGX_GetParam("CONTENT_LENGTH", request->envp)
67 << "\"\n";
68 clen = STDIN_MAX;
72 // Note that *you* should not read stdin when CONTENT_LENGTH
73 // is missing or unparsable (this is a demo/test program).
75 // *always* put a cap on the amount of data that will be read
76 if (clen > STDIN_MAX) clen = STDIN_MAX;
78 *content = new char[clen];
80 cin.read(*content, clen);
81 clen = cin.gcount();
83 // chew up any remaining stdin - this shouldn't be necessary
84 // but is because mod_fastcgi doesn't handle it correctly
85 do cin.ignore(1024); while (! cin.eof());
87 return clen;
90 int main (void)
92 int count = 0;
93 long pid = getpid();
95 FCGX_Request request;
97 FCGX_Init();
98 FCGX_InitRequest(&request, 0, 0);
100 while (FCGX_Accept_r(&request) == 0)
102 // Note that the default bufsize (0) will cause the use of iostream
103 // methods that require positioning (such as peek(), seek(),
104 // unget() and putback()) to fail (in favour of more efficient IO).
105 fcgi_streambuf fin(request.in);
106 fcgi_streambuf fout(request.out);
107 fcgi_streambuf ferr(request.err);
109 #ifdef _WIN32
110 cin = &fin;
111 cout = &fout;
112 cerr = &ferr;
113 #else
114 cin.rdbuf(&fin);
115 cout.rdbuf(&fout);
116 cerr.rdbuf(&ferr);
117 #endif
119 // Although FastCGI supports writing before reading,
120 // many http clients (browsers) don't support it (so
121 // the connection deadlocks until a timeout expires!).
122 char * content;
123 unsigned long clen = gstdin(&request, &content);
125 cout << "Content-type: text/html\r\n"
126 "\r\n"
127 "<TITLE>echo-cpp</TITLE>\n"
128 "<H1>echo-cpp</H1>\n"
129 "<H4>PID: " << pid << "</H4>\n"
130 "<H4>Request Number: " << ++count << "</H4>\n";
132 cout << "<H4>Request Environment</H4>\n";
133 penv(request.envp);
135 cout << "<H4>Process/Initial Environment</H4>\n";
136 penv(environ);
138 cout << "<H4>Standard Input - " << clen;
139 if (clen == STDIN_MAX) cout << " (STDIN_MAX)";
140 cout << " bytes</H4>\n";
141 if (clen) cout.write(content, clen);
143 if (content) delete []content;
145 // If the output streambufs had non-zero bufsizes and
146 // were constructed outside of the accept loop (i.e.
147 // their destructor won't be called here), they would
148 // have to be flushed here.
151 return 0;