sys/src/cmd/exportfs/pattern.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <fcall.h>
   4 #include <bio.h>
   5 #include <regexp.h>
   6 #define Extern
   7 #include "exportfs.h"
   8
   9 Reprog  **exclude, **include;
  10 char    *patternfile;
  11
  12 void
  13 exclusions(void)
  14 {
  15         Biobuf *f;
  16         int ni, nmaxi, ne, nmaxe;
  17         char *line;
  18
  19         if(patternfile == nil)
  20                 return;
  21
  22         f = Bopen(patternfile, OREAD);
  23         if(f == nil)
  24                 fatal("cannot open patternfile");
  25         ni = 0;
  26         nmaxi = 100;
  27         include = malloc(nmaxi*sizeof(*include));
  28         if(include == nil)
  29                 fatal("out of memory");
  30         include[0] = nil;
  31         ne = 0;
  32         nmaxe = 100;
  33         exclude = malloc(nmaxe*sizeof(*exclude));
  34         if(exclude == nil)
  35                 fatal("out of memory");
  36         exclude[0] = nil;
  37         while(line = Brdline(f, '\n')){
  38                 line[Blinelen(f) - 1] = 0;
  39                 if(strlen(line) < 2 || line[1] != ' ')
  40                         continue;
  41                 switch(line[0]){
  42                 case '+':
  43                         if(ni+1 >= nmaxi){
  44                                 nmaxi = 2*nmaxi;
  45                                 include = realloc(include, nmaxi*sizeof(*include));
  46                                 if(include == nil)
  47                                         fatal("out of memory");
  48                         }
  49                         DEBUG(DFD, "\tinclude %s\n", line+2);
  50                         include[ni] = regcomp(line+2);
  51                         include[++ni] = nil;
  52                         break;
  53                 case '-':
  54                         if(ne+1 >= nmaxe){
  55                                 nmaxe = 2*nmaxe;
  56                                 exclude = realloc(exclude, nmaxe*sizeof(*exclude));
  57                                 if(exclude == nil)
  58                                         fatal("out of memory");
  59                         }
  60                         DEBUG(DFD, "\texclude %s\n", line+2);
  61                         exclude[ne] = regcomp(line+2);
  62                         exclude[++ne] = nil;
  63                         break;
  64                 default:
  65                         DEBUG(DFD, "ignoring pattern %s\n", line);
  66                         break;
  67                 }
  68         }
  69         Bterm(f);
  70 }
  71
  72 int
  73 excludefile(char *path)
  74 {
  75         Reprog **re;
  76         char *p;
  77
  78         if(*(path+1) == 0)
  79                 p = "/";
  80         else
  81                 p = path+1;
  82
  83         DEBUG(DFD, "checking %s\n", p);
  84         for(re = include; *re != nil; re++){
  85                 if(regexec(*re, p, nil, 0) != 1){
  86                         DEBUG(DFD, "excluded+ %s\n", p);
  87                         return -1;
  88                 }
  89         }
  90         for(re = exclude; *re != nil; re++){
  91                 if(regexec(*re, p, nil, 0) == 1){
  92                         DEBUG(DFD, "excluded- %s\n", p);
  93                         return -1;
  94                 }
  95         }
  96         return 0;
  97 }
  98
  99 int
 100 preaddir(Fid *f, uchar *data, int n, vlong offset)
 101 {
 102         int r = 0, m;
 103         Dir *d;
 104
 105         DEBUG(DFD, "\tpreaddir n=%d wo=%lld fo=%lld\n", n, offset, f->offset);
 106         if(offset == 0 && f->offset != 0){
 107                 if(seek(f->fid, 0, 0) != 0)
 108                         return -1;
 109                 f->offset = f->cdir = f->ndir = 0;
 110                 free(f->dir);
 111                 f->dir = nil;
 112         }else if(offset != f->offset){
 113                 werrstr("can't seek dir %lld to %lld", f->offset, offset);
 114                 return -1;
 115         }
 116
 117         while(n > 0){
 118                 if(f->dir == nil){
 119                         f->ndir = dirread(f->fid, &f->dir);
 120                         if(f->ndir < 0)
 121                                 return f->ndir;
 122                         if(f->ndir == 0)
 123                                 return r;
 124                 }
 125                 d = &f->dir[f->cdir++];
 126                 if(exclude){
 127                         char *p = makepath(f->f, d->name);
 128                         if(excludefile(p)){
 129                                 free(p);
 130                                 goto skipentry;
 131                         }
 132                         free(p);
 133                 }
 134                 m = convD2M(d, data, n);
 135                 DEBUG(DFD, "\t\tconvD2M %d\n", m);
 136                 if(m <= BIT16SZ){
 137                         DEBUG(DFD, "\t\t\tneeded %d\n", GBIT16(data));
 138                         /* not enough room for full entry; leave for next time */
 139                         f->cdir--;
 140                         return r;
 141                 }else{
 142                         data += m;
 143                         n -= m;
 144                         r += m;
 145                         f->offset += m;
 146                 }
 147 skipentry:      if(f->cdir >= f->ndir){
 148                         f->cdir = f->ndir = 0;
 149                         free(f->dir);
 150                         f->dir = nil;
 151                 }
 152         }
 153         return r;
 154 }