sys/src/cmd/ip/httpd/netlib_history.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <bio.h>
   4 #include "httpd.h"
   5 #include "httpsrv.h"
   6
   7 Hio *HO;
   8 int diffb;
   9
  10 enum{ DAY = 24*60*60 };
  11
  12 void
  13 lastbefore(ulong t, char *f, char *b)
  14 {
  15         Tm *tm;
  16         Dir *dir;
  17         int try;
  18         ulong t0, mtime;
  19
  20         t0 = t;
  21         for(try=0; try<10; try++) {
  22                 tm = localtime(t);
  23                 t -= DAY;
  24                 sprint(b,"%.4d/%.2d%.2d/netlib/pub/%s",tm->year+1900,tm->mon+1,tm->mday,f);
  25                 dir = dirstat(b);
  26                 if(dir == nil)
  27                         continue;
  28                 mtime = dir->mtime;
  29                 free(dir);
  30                 if(mtime > t0)
  31                         continue;
  32                 return;
  33         }
  34         strcpy(b, "filenotfound");
  35 }
  36
  37 // create explicit file for diff, which otherwise would create a
  38 // mode 0600 file that it couldn't read (because running as none)
  39 void
  40 gunzip(char *f, char *tmp)
  41 {
  42         int fd = open(tmp, OWRITE);
  43
  44         if(fd < 0)  // can't happen
  45                 return;
  46         switch(fork()){
  47         case 0:
  48                 dup(fd, 1);
  49                 close(fd);
  50                 close(0);
  51                 execl("/bin/gunzip", "gunzip", "-c", f, nil);
  52                 hprint(HO, "can't exec gunzip: %r\n");
  53                 break;
  54         case -1:
  55                 hprint(HO, "fork failed: %r\n");
  56         default:
  57                 while(waitpid() != -1)
  58                         ;
  59                 break;
  60         }
  61         close(fd);
  62 }
  63
  64 void
  65 netlibhistory(char *file)
  66 {
  67         char buf[500], pair[2][500], tmpf[2][30], *f;
  68         int toggle = 0, started = 0, limit;
  69         Dir *dir;
  70         ulong otime, dt;
  71         int i, fd, tmpcnt;
  72
  73         if(strncmp(file, "../", 3) == 0 || strstr(file, "/../") ||
  74                 strlen(file) >= sizeof(buf) - strlen("1997/0204/netlib/pub/0"))
  75                 return;
  76         limit = 50;
  77         if(diffb){
  78                 limit = 10;
  79                 // create two tmp files for gunzip
  80                 for(i = 0, tmpcnt = 0; i < 2 && tmpcnt < 20; tmpcnt++){
  81                         snprint(tmpf[i], sizeof(tmpf[0]), "/tmp/d%x", tmpcnt);
  82                         if(access(buf, AEXIST) == 0)
  83                                 continue;
  84                         fd = create(tmpf[i], OWRITE, 0666);
  85                         if(fd < 0)
  86                                 goto done;
  87                         close(fd);
  88                         i++;
  89                 }
  90         }
  91         otime = time(0);
  92         hprint(HO,"<UL>\n");
  93         while(limit--){
  94                 lastbefore(otime, file, buf);
  95                 dir = dirstat(buf);
  96                 if(dir == nil)
  97                         goto done;
  98                 dt = DAY/2;
  99                 while(otime <= dir->mtime){
 100                         lastbefore(otime-dt, file, buf);
 101                         free(dir);
 102                         dir = dirstat(buf);
 103                         if(dir == nil)
 104                                 goto done;
 105                         dt += DAY/2;
 106                 }
 107                 f = pair[toggle];
 108                 strcpy(f, buf);
 109                 if(diffb && strcmp(f+strlen(f)-3, ".gz") == 0){
 110                         gunzip(f, tmpf[toggle]);
 111                         strcpy(f, tmpf[toggle]);
 112                 }
 113                 if(diffb && started){
 114                         hprint(HO, "<PRE>\n");
 115                         hflush(HO);
 116                         switch(fork()){
 117                         case 0:
 118                                 execl("/bin/diff", "diff", "-nb",
 119                                         pair[1-toggle], pair[toggle], nil);
 120                                 hprint(HO, "can't exec diff: %r\n");
 121                                 break;
 122                         case -1:
 123                                 hprint(HO, "fork failed: %r\n");
 124                                 break;
 125                         default:
 126                                 while(waitpid() != -1)
 127                                         ;
 128                                 break;
 129                         }
 130                         hprint(HO, "</PRE>\n");
 131                 }
 132                 hprint(HO,"<LI><A HREF=\"/historic/%s\">%s</A> %lld bytes\n",
 133                         buf, 4+asctime(gmtime(dir->mtime)), dir->length);
 134                 if(diffb)
 135                         hprint(HO," <FONT SIZE=-1>(%s)</FONT>\n", pair[toggle]);
 136                 toggle = 1-toggle;
 137                 started = 1;
 138                 otime = dir->mtime;
 139                 free(dir);
 140         }
 141         hprint(HO,"<LI>...\n");
 142 done:
 143         hprint(HO,"</UL>\n");
 144         if(diffb){
 145                 remove(tmpf[0]);
 146                 remove(tmpf[1]);
 147         }
 148 }
 149
 150 int
 151 send(HConnect *c)
 152 {
 153         char *file, *s;
 154         HSPairs *q;
 155
 156         if(strcmp(c->req.meth, "GET") != 0 && strcmp(c->req.meth, "HEAD") != 0)
 157                 return hunallowed(c, "GET, HEAD");
 158         if(c->head.expectother || c->head.expectcont)
 159                 return hfail(c, HExpectFail, nil);
 160         if(c->req.search == nil || !*c->req.search)
 161                 return hfail(c, HNoData, "netlib_history");
 162         s = c->req.search;
 163         while((s = strchr(s, '+')) != nil)
 164                 *s++ = ' ';
 165         file = nil;
 166         for(q = hparsequery(c, hstrdup(c, c->req.search)); q; q = q->next){
 167                 if(strcmp(q->s, "file") == 0)
 168                         file = q->t;
 169                 else if(strcmp(q->s, "diff") == 0)
 170                         diffb = 1;
 171         }
 172         if(file == nil)
 173                 return hfail(c, HNoData, "netlib_history missing file field");
 174         logit(c, "netlib_hist %s%s", file, diffb?" DIFF":"");
 175
 176         if(c->req.vermaj){
 177                 hokheaders(c);
 178                 hprint(HO, "Content-type: text/html\r\n");
 179                 hprint(HO, "\r\n");
 180         }
 181         if(strcmp(c->req.meth, "HEAD") == 0){
 182                 writelog(c, "Reply: 200 netlib_history 0\n");
 183                 hflush(HO);
 184                 exits(nil);
 185         }
 186
 187         hprint(HO, "<HEAD><TITLE>%s history</TITLE></HEAD>\n<BODY>\n",file);
 188         hprint(HO, "<H2>%s history</H2>\n",file);
 189         hprint(HO, "<I>Netlib's copy of %s was changed\n", file);
 190         hprint(HO, "on the dates shown.  <BR>Click on the date link\n");
 191         hprint(HO, "to retrieve the corresponding version.</I>\n");
 192         if(diffb){
 193                 hprint(HO, "<BR><I>Lines beginning with &lt; are for the\n");
 194                 hprint(HO, "newer of the two versions.</I>\n");
 195         }
 196
 197         if(chdir("/usr/web/historic") < 0)
 198                 hprint(HO, "chdir failed: %r\n");
 199         netlibhistory(file);
 200
 201         hprint(HO, "<BR><A HREF=\"http://cm.bell-labs.com/who/ehg\">Eric Grosse</A>\n");
 202         hprint(HO, "</BODY></HTML>\n");
 203         hflush(HO);
 204         writelog(c, "Reply: 200 netlib_history %ld %ld\n", HO->seek, HO->seek);
 205         return 1;
 206 }
 207
 208 void
 209 main(int argc, char **argv)
 210 {
 211         HConnect *c;
 212
 213         c = init(argc, argv);
 214         HO = &c->hout;
 215         if(hparseheaders(c, HSTIMEOUT) >= 0)
 216                 send(c);
 217         exits(nil);
 218 }