/* cgilib.cpp - A simple library I wrote in high school to make it easier to write CGI scripts. It's ancient code, and probably sucks. Such is the nature of life... Uses some code snatched from NCSA at some point. Copyright (C) 1995, 1996, 2000 Piotr F. Mitros This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Contact: pmitros@mit.edu. After 2001, hopefully pmitros@alum.mit.edu :) */ // This is the CGI script for a TITLE #include #include #include #include #include "cgilib.h" // CGI entries entry *Entries; int cEntries; void DebugMsg(char*Text) { FILE*file; file=fopen("d:\\www\\Debug", "a"); fprintf(file, "\n%s", Text); fclose(file); } void BeginPage(char*Title) { // Header printf("Content-type: text/html%c%c",LF,LF); // Specify return type puts(""); printf("%s\n", Title); puts(""); } void EndPage() { puts("

Back to main page.

"); puts("\n"); } //////////////////////////////////////////////////////////// // Misc. Routines void ErrorMsg(char*Error) { printf("Content-type: text/html%c%c",LF,LF); // Specify return type puts(""); puts("Error Message for CGI program"); puts(""); puts("

Error Message

"); puts("

By Piotr Mitros

"); puts("

Congratulations! You have either:
"); puts("a) Found a mistake in a bullet-proof" " CGI Program by Piotr F. Mitros
"); puts("\tor
"); puts("b) Made a mistake

"); puts("
"); puts("

Your error is:

Drum roll, please: "); puts(Error); puts("

\n"); exit(0); } //////////////////////////////////////////////////////////// // CGI routines - debugged char* GetEntry(char* Entry) { int i=0; if(cEntries==0) return NULL; while(strcmp(Entries[i].name, Entry)) { i++; if(i==cEntries) return NULL; } return Entries[i].val; } void ReadCGIEntries() { cEntries=0; char*ReqMethod=getenv("REQUEST_METHOD"); int PostMethod=strcmp(ReqMethod, "POST"); if(PostMethod) return; if(strcmp(getenv("CONTENT_TYPE"), "application/x-www-form-urlencoded")) ErrorMsg("This application can only take form data."); // Yes, I know the standard says that CGI input doesn't have // to end with an EOF. But it always does. I hope. int cl = atoi(getenv("CONTENT_LENGTH")); for(int x=0;cl && (!feof(stdin));x++) { entry ce; // Current entry ce.val = fmakeword(stdin,'&',&cl); plustospace(ce.val); unescape_url(ce.val); ce.name = makeword(ce.val,'='); AddEntry(ce); } } // This code is very slow. It deallocates, copies, and // reallocates the block of memory each iteration. But // who cares? Its fast enough on any decent computer, // and I'm (hopefully) not paying (much) for CPU time. // Seriously, considering 20 entries max, it won't take // too long. void AddEntry(entry ce) { ++cEntries; Entries=(entry*)realloc(Entries, sizeof(entry)*cEntries); if(Entries==NULL) ErrorMsg("Out of Memory. " "(On server side, there's nothing you can do about it)"); memcpy(&Entries[cEntries-1], &ce, sizeof(entry)); } ////////////////////////////////////////////////////////// // Misc. functions stolen from NCSA code on their web site, optimized a bit. void getword(char *word, char *line, char stop) { int x = 0,y; for(x=0;((line[x]) && (line[x] != stop));x++) word[x] = line[x]; word[x] = '\0'; if(line[x]) ++x; y=0; while(line[y++] = line[x++]); } char *makeword(char *line, char stop) { int x = 0,y; char *word = (char *) malloc(sizeof(char) * (strlen(line) + 1)); for(x=0;((line[x]) && (line[x] != stop));x++) word[x] = line[x]; word[x] = '\0'; if(line[x]) ++x; y=0; while(line[y++] = line[x++]) NULL; return word; } char *fmakeword(FILE *f, char stop, int *cl) { int wsize; char *word; int ll; wsize = 102400; ll=0; word = (char *) malloc(sizeof(char) * (wsize + 1)); while(1) { word[ll] = (char)fgetc(f); if(ll==wsize) { word[ll+1] = '\0'; wsize+=102400; word = (char *)realloc(word,sizeof(char)*(wsize+1)); } --(*cl); if((word[ll] == stop) || (feof(f)) || (!(*cl))) { if(word[ll] != stop) ll++; word[ll] = '\0'; // return word; return realloc(word, sizeof(char)*(ll+1)); } ++ll; } } char x2c(char *what) { register char digit; digit = (what[0] >= 'A' ? ((what[0] & 0xdf) - 'A')+10 : (what[0] - '0')); digit *= 16; digit += (what[1] >= 'A' ? ((what[1] & 0xdf) - 'A')+10 : (what[1] - '0')); return(digit); } void unescape_url(char *url) { register int x,y; for(x=0,y=0;url[y];++x,++y) { if((url[x] = url[y]) == '%') { url[x] = x2c(&url[y+1]); y+=2; } } url[x] = '\0'; } void plustospace(char *str) { register int x; for(x=0;str[x];x++) if(str[x] == '+') str[x] = ' '; } int rind(char *s, char c) { register int x; for(x=strlen(s) - 1;x != -1; x--) if(s[x] == c) return x; return -1; } int getline(char *s, int n, FILE *f) { register int i=0; while(1) { s[i] = (char)fgetc(f); if(s[i] == CR) s[i] = fgetc(f); if((s[i] == 0x4) || (s[i] == LF) || (i == (n-1))) { s[i] = '\0'; return (feof(f) ? 1 : 0); } ++i; } } void send_fd(FILE *f, FILE *fd) { int num_chars=0; char c; while (1) { c = fgetc(f); if(feof(f)) return; fputc(c,fd); } } int ind(char *s, char c) { register int x; for(x=0;s[x];x++) if(s[x] == c) return x; return -1; } void escape_shell_cmd(char *cmd) { register int x,y,l; l=strlen(cmd); for(x=0;cmd[x];x++) { if(ind("&;`'\"|*?~<>^()[]{}$\\",cmd[x]) != -1) { for(y=l+1;y>x;y--) cmd[y] = cmd[y-1]; l++; /* length has been increased */ cmd[x] = '\\'; x++; /* skip the character */ } } }