Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include <bio.h>
#include "httpd.h"
#include "httpsrv.h"

Hio *HO;
int diffb;

enum{ DAY = 24*60*60 };

void
lastbefore(ulong t, char *f, char *b)
{
        Tm *tm;
        Dir *dir;
        int try;
        ulong t0, mtime;

        t0 = t;
        for(try=0; try<10; try++) {
                tm = localtime(t);
                t -= DAY;
                sprint(b,"%.4d/%.2d%.2d/netlib/pub/%s",tm->year+1900,tm->mon+1,tm->mday,f);
                dir = dirstat(b);
                if(dir == nil)
                        continue;
                mtime = dir->mtime;
                free(dir);
                if(mtime > t0)
                        continue;
                return;
        }
        strcpy(b, "filenotfound");
}

// create explicit file for diff, which otherwise would create a
// mode 0600 file that it couldn't read (because running as none)
void
gunzip(char *f, char *tmp)
{
        int fd = open(tmp, OWRITE);

        if(fd < 0)  // can't happen
                return;
        switch(fork()){
        case 0:
                dup(fd, 1);
                close(fd);
                close(0);
                execl("/bin/gunzip", "gunzip", "-c", f, nil);
                hprint(HO, "can't exec gunzip: %r\n");
                break;
        case -1:
                hprint(HO, "fork failed: %r\n");
        default:
                while(waitpid() != -1)
                        ;
                break;
        }
        close(fd);
}

void
netlibhistory(char *file)
{
        char buf[500], pair[2][500], tmpf[2][30], *f;
        int toggle = 0, started = 0, limit;
        Dir *dir;
        ulong otime, dt;
        int i, fd, tmpcnt;

        if(strncmp(file, "../", 3) == 0 || strstr(file, "/../") ||
                strlen(file) >= sizeof(buf) - strlen("1997/0204/netlib/pub/0"))
                return;
        limit = 50;
        if(diffb){
                limit = 10;
                // create two tmp files for gunzip
                for(i = 0, tmpcnt = 0; i < 2 && tmpcnt < 20; tmpcnt++){
                        snprint(tmpf[i], sizeof(tmpf[0]), "/tmp/d%x", tmpcnt);
                        if(access(buf, AEXIST) == 0)
                                continue;
                        fd = create(tmpf[i], OWRITE, 0666);
                        if(fd < 0)
                                goto done;
                        close(fd);
                        i++;
                }
        }
        otime = time(0);
        hprint(HO,"<UL>\n");
        while(limit--){
                lastbefore(otime, file, buf);
                dir = dirstat(buf);
                if(dir == nil)
                        goto done;
                dt = DAY/2;
                while(otime <= dir->mtime){
                        lastbefore(otime-dt, file, buf);
                        free(dir);
                        dir = dirstat(buf);
                        if(dir == nil)
                                goto done;
                        dt += DAY/2;
                }
                f = pair[toggle];
                strcpy(f, buf);
                if(diffb && strcmp(f+strlen(f)-3, ".gz") == 0){
                        gunzip(f, tmpf[toggle]);
                        strcpy(f, tmpf[toggle]);
                }
                if(diffb && started){
                        hprint(HO, "<PRE>\n");
                        hflush(HO);
                        switch(fork()){
                        case 0:
                                execl("/bin/diff", "diff", "-nb",
                                        pair[1-toggle], pair[toggle], nil);
                                hprint(HO, "can't exec diff: %r\n");
                                break;
                        case -1:
                                hprint(HO, "fork failed: %r\n");
                                break;
                        default:
                                while(waitpid() != -1)
                                        ;
                                break;
                        }
                        hprint(HO, "</PRE>\n");
                }
                hprint(HO,"<LI><A HREF=\"/historic/%s\">%s</A> %lld bytes\n",
                        buf, 4+asctime(gmtime(dir->mtime)), dir->length);
                if(diffb)
                        hprint(HO," <FONT SIZE=-1>(%s)</FONT>\n", pair[toggle]);
                toggle = 1-toggle;
                started = 1;
                otime = dir->mtime;
                free(dir);
        }
        hprint(HO,"<LI>...\n");
done:
        hprint(HO,"</UL>\n");
        if(diffb){
                remove(tmpf[0]);
                remove(tmpf[1]);
        }
}

int
send(HConnect *c)
{
        char *file, *s;
        HSPairs *q;

        if(strcmp(c->req.meth, "GET") != 0 && strcmp(c->req.meth, "HEAD") != 0)
                return hunallowed(c, "GET, HEAD");
        if(c->head.expectother || c->head.expectcont)
                return hfail(c, HExpectFail, nil);
        if(c->req.search == nil || !*c->req.search)
                return hfail(c, HNoData, "netlib_history");
        s = c->req.search;
        while((s = strchr(s, '+')) != nil)
                *s++ = ' ';
        file = nil;
        for(q = hparsequery(c, hstrdup(c, c->req.search)); q; q = q->next){
                if(strcmp(q->s, "file") == 0)
                        file = q->t;
                else if(strcmp(q->s, "diff") == 0)
                        diffb = 1;
        }
        if(file == nil)
                return hfail(c, HNoData, "netlib_history missing file field");
        logit(c, "netlib_hist %s%s", file, diffb?" DIFF":"");

        if(c->req.vermaj){
                hokheaders(c);
                hprint(HO, "Content-type: text/html\r\n");
                hprint(HO, "\r\n");
        }
        if(strcmp(c->req.meth, "HEAD") == 0){
                writelog(c, "Reply: 200 netlib_history 0\n");
                hflush(HO);
                exits(nil);
        }

        hprint(HO, "<HEAD><TITLE>%s history</TITLE></HEAD>\n<BODY>\n",file);
        hprint(HO, "<H2>%s history</H2>\n",file);
        hprint(HO, "<I>Netlib's copy of %s was changed\n", file);
        hprint(HO, "on the dates shown.  <BR>Click on the date link\n");
        hprint(HO, "to retrieve the corresponding version.</I>\n");
        if(diffb){
                hprint(HO, "<BR><I>Lines beginning with &lt; are for the\n");
                hprint(HO, "newer of the two versions.</I>\n");
        }

        if(chdir("/usr/web/historic") < 0)
                hprint(HO, "chdir failed: %r\n");
        netlibhistory(file);

        hprint(HO, "<BR><A HREF=\"http://cm.bell-labs.com/who/ehg\">Eric Grosse</A>\n");
        hprint(HO, "</BODY></HTML>\n");
        hflush(HO);
        writelog(c, "Reply: 200 netlib_history %ld %ld\n", HO->seek, HO->seek);
        return 1;
}

void
main(int argc, char **argv)
{
        HConnect *c;

        c = init(argc, argv);
        HO = &c->hout;
        if(hparseheaders(c, HSTIMEOUT) >= 0)
                send(c);
        exits(nil);
}