Edit File: rredir.c
/* * Copyright (C) 1996-2016 The Squid Software Foundation and contributors * * Squid software is distributed under GPLv2+ license and includes * contributions from numerous individuals and organizations. * Please see the COPYING and CONTRIBUTORS files for details. * */ #include "squid.h" /* * From: richard@hekkihek.hacom.nl (Richard Huveneers) * To: squid-users@nlanr.net * Subject: Save 15% on your bandwidth... * Date: 12 Sep 1996 21:21:55 GMT * =========================================================================== * * I have downloaded the multi-megabyte files from Netscape and Microsoft * that our users like to download from every mirror in the world, * defeating the usual caching. * * I put these files in a separate directory and installed a basic * redirector for Squid that checks if the file (so hostname and pathname * are disregarded) is present in this directory. * * After a few days of testing (the redirector looks very stable) it looks * like this is saving us approx. 15% on our cache flow. Also, our own WWW * server has become more popular than ever :) * * I'm sure this code will be useful to others too, so I've attached it at * the end of this message. Improvements, extensions etc. are welcome. * * I'm going on holidays now, so I won't be able to respond to e-mail * quickly. * * Enjoy, Richard. */ /* * rredir - redirect to local directory * * version 0.1, 7 sep 1996 * - initial version (Richard Huveneers <Richard.Huveneers@hekkihek.hacom.nl>) */ #include <unistd.h> #include <string.h> #include <ctype.h> #define ACCESS_LOCAL_DIR "/var/lib/httpd/htdocs/local/rredir" #define REDIRECT_TO_URL "http://www.hacom.nl/local/rredir" #define BUFFER_SIZE (16*1024) int main() { char buf[BUFFER_SIZE]; char *s, *t; int tlu = 0; /* make standard output line buffered */ if (setvbuf(stdout, NULL, _IOLBF, 0) != 0) return 1; /* speed up the access() calls below */ if (chdir(ACCESS_LOCAL_DIR) == -1) return 1; /* scan standard input */ while (fgets(buf, BUFFER_SIZE, stdin) != NULL) { /* check for too long urls */ if (strchr(buf, '\n') == NULL) { tlu = 1; continue; } if (tlu) goto dont_redirect; /* determine end of url */ if ((s = strchr(buf, ' ')) == NULL) goto dont_redirect; *s = '\0'; /* determine first character of filename */ if ((s = strrchr(buf, '/')) == NULL) goto dont_redirect; s++; /* security: do not redirect to hidden files, the current * directory or the parent directory */ if (*s == '.' || *s == '\0') goto dont_redirect; /* map filename to lower case */ for (t = s; *t != '\0'; t++) *t = (char) tolower((int) *t); /* check for a local copy of this file */ if (access(s, R_OK) == 0) { (void) printf("%s/%s\n", REDIRECT_TO_URL, s); continue; } dont_redirect: tlu = 0; (void) printf("\n"); } return 0; }