networking/httpd_ssi.c

   1 /*
   2  * Copyright (c) 2009 Denys Vlasenko <vda.linux@googlemail.com>
   3  *
   4  * Licensed under GPLv2, see file LICENSE in this tarball for details.
   5  */
   6
   7 /*
   8  * This program is a CGI application. It processes server-side includes:
   9  * <!--#include file="file.html" -->
  10  *
  11  * Usage: put these lines in httpd.conf:
  12  *
  13  * *.html:/bin/httpd_ssi
  14  * *.htm:/bin/httpd_ssi
  15  */
  16
  17 /* Build a-la
  18 i486-linux-uclibc-gcc \
  19 -static -static-libgcc \
  20 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 \
  21 -Wall -Wshadow -Wwrite-strings -Wundef -Wstrict-prototypes -Werror \
  22 -Wold-style-definition -Wdeclaration-after-statement -Wno-pointer-sign \
  23 -Wmissing-prototypes -Wmissing-declarations \
  24 -Os -fno-builtin-strlen -finline-limit=0 -fomit-frame-pointer \
  25 -ffunction-sections -fdata-sections -fno-guess-branch-probability \
  26 -funsigned-char \
  27 -falign-functions=1 -falign-jumps=1 -falign-labels=1 -falign-loops=1 \
  28 -march=i386 -mpreferred-stack-boundary=2 \
  29 -Wl,-Map -Wl,link.map -Wl,--warn-common -Wl,--sort-common -Wl,--gc-sections \
  30 httpd_ssi.c -o httpd_ssi
  31 */
  32
  33 /* Size (i386, static uclibc, approximate):
  34    text    data     bss     dec     hex filename
  35    8931     164   68552   77647   12f4f httpd_ssi
  36 */
  37
  38 #include <sys/types.h>
  39 #include <sys/stat.h>
  40 #include <errno.h>
  41 #include <stdint.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <unistd.h>
  45 #include <stdio.h>
  46 #include <dirent.h>
  47 #include <time.h>
  48
  49 static char line[64 * 1024];
  50
  51 /*
  52  * Currently only handles directives which are alone on the line
  53  */
  54 static void process_includes(const char *filename)
  55 {
  56         FILE *fp = fopen(filename, "r");
  57         if (!fp)
  58                 exit(1);
  59
  60 #define INCLUDE "<!--#include file=\""
  61         while (fgets(line, sizeof(line), fp)) {
  62                 char *closing_dq;
  63
  64                 /* FIXME: output text leading to INCLUDE first */
  65                 if (strncmp(line, INCLUDE, sizeof(INCLUDE)-1) != 0
  66                  || (closing_dq = strchr(line + sizeof(INCLUDE)-1, '"')) == NULL
  67                 /* or strstr(line + sizeof(INCLUDE)-1, "\" -->")? */
  68                 ) {
  69                         fputs(line, stdout);
  70                         continue;
  71                 }
  72                 *closing_dq = '\0';
  73                 /* FIXME:
  74                  * (1) are relative paths with /../ etc ok?
  75                  * (2) if we include a/1.htm and it includes b/2.htm,
  76                  * do we need to include a/b/2.htm or b/2.htm?
  77                  * IOW, do we need to "cd $dirname"?
  78                  */
  79                 process_includes(line + sizeof(INCLUDE)-1);
  80                 /* FIXME: this should be the tail of line after --> */
  81                 putchar('\n');
  82         }
  83 }
  84
  85 int main(int argc, char *argv[])
  86 {
  87         if (!argv[1])
  88                 return 1;
  89
  90         /* Seen from busybox.net's Apache:
  91          * HTTP/1.1 200 OK
  92          * Date: Thu, 10 Sep 2009 18:23:28 GMT
  93          * Server: Apache
  94          * Accept-Ranges: bytes
  95          * Connection: close
  96          * Content-Type: text/html
  97          */
  98         printf(
  99                 /* "Date: Thu, 10 Sep 2009 18:23:28 GMT\r\n" */
 100                 /* "Server: Apache\r\n" */
 101                 /* "Accept-Ranges: bytes\r\n" - do we really accept bytes?! */
 102                 "Connection: close\r\n"
 103                 "Content-Type: text/html\r\n"
 104                 "\r\n"
 105         );
 106         process_includes(argv[1]);
 107         return 0;
 108 }