sys/src/cmd/mv.c

   1 #include <u.h>
   2 #include <libc.h>
   3
   4 int     copy1(int fdf, int fdt, char *from, char *to);
   5 void    hardremove(char *);
   6 int     mv(char *from, char *todir, char *toelem);
   7 int     mv1(char *from, Dir *dirb, char *todir, char *toelem);
   8 int     samefile(char *, char *);
   9 void    split(char *, char **, char **);
  10
  11 void
  12 main(int argc, char *argv[])
  13 {
  14         int i, failed;
  15         Dir *dirto, *dirfrom;
  16         char *todir, *toelem;
  17
  18         if(argc<3){
  19                 fprint(2, "usage: mv fromfile tofile\n");
  20                 fprint(2, "       mv fromfile ... todir\n");
  21                 exits("bad usage");
  22         }
  23
  24         /* prepass to canonicalise names before splitting, etc. */
  25         for(i=1; i < argc; i++)
  26                 cleanname(argv[i]);
  27
  28         if((dirto = dirstat(argv[argc-1])) != nil && (dirto->mode&DMDIR)){
  29                 dirfrom = nil;
  30                 if(argc == 3
  31                 && (dirfrom = dirstat(argv[1])) != nil
  32                 && (dirfrom->mode & DMDIR))
  33                         split(argv[argc-1], &todir, &toelem); /* mv dir1 dir2 */
  34                 else{                           /* mv file... dir */
  35                         todir = argv[argc-1];
  36                         toelem = nil;           /* toelem will be fromelem */
  37                 }
  38                 free(dirfrom);
  39         }else
  40                 split(argv[argc-1], &todir, &toelem);   /* mv file1 file2 */
  41         free(dirto);
  42         if(argc>3 && toelem != nil){
  43                 fprint(2, "mv: %s not a directory\n", argv[argc-1]);
  44                 exits("bad usage");
  45         }
  46
  47         failed = 0;
  48         for(i=1; i < argc-1; i++)
  49                 if(mv(argv[i], todir, toelem) < 0)
  50                         failed++;
  51         if(failed)
  52                 exits("failure");
  53         exits(0);
  54 }
  55
  56 int
  57 mv(char *from, char *todir, char *toelem)
  58 {
  59         int stat;
  60         Dir *dirb;
  61
  62         dirb = dirstat(from);
  63         if(dirb == nil){
  64                 fprint(2, "mv: can't stat %s: %r\n", from);
  65                 return -1;
  66         }
  67         stat = mv1(from, dirb, todir, toelem);
  68         free(dirb);
  69         return stat;
  70 }
  71
  72 int
  73 mv1(char *from, Dir *dirb, char *todir, char *toelem)
  74 {
  75         int fdf, fdt, i, j, stat;
  76         char toname[4096], fromname[4096];
  77         char *fromdir, *fromelem;
  78         Dir *dirt, null;
  79
  80         strncpy(fromname, from, sizeof fromname);
  81         split(from, &fromdir, &fromelem);
  82         if(toelem == 0)
  83                 toelem = fromelem;
  84         i = strlen(toelem);
  85         if(i==0){
  86                 fprint(2, "mv: null last name element moving %s\n", fromname);
  87                 return -1;
  88         }
  89         j = strlen(todir);
  90         if(i + j + 2 > sizeof toname){
  91                 fprint(2, "mv: path too big (max %d): %s/%s\n",
  92                         sizeof toname, todir, toelem);
  93                 return -1;
  94         }
  95         memmove(toname, todir, j);
  96         toname[j] = '/';
  97         memmove(toname+j+1, toelem, i);
  98         toname[i+j+1] = 0;
  99
 100         if(samefile(fromdir, todir)){
 101                 if(samefile(fromname, toname)){
 102                         fprint(2, "mv: %s and %s are the same\n",
 103                                 fromname, toname);
 104                         return -1;
 105                 }
 106
 107                 /* remove target if present */
 108                 dirt = dirstat(toname);
 109                 if(dirt != nil) {
 110                         hardremove(toname);
 111                         free(dirt);
 112                 }
 113
 114                 /* try wstat */
 115                 nulldir(&null);
 116                 null.name = toelem;
 117                 if(dirwstat(fromname, &null) >= 0)
 118                         return 0;
 119                 if(dirb->mode & DMDIR){
 120                         fprint(2, "mv: can't rename directory %s: %r\n",
 121                                 fromname);
 122                         return -1;
 123                 }
 124         }
 125         /*
 126          * Renaming won't work --- must copy
 127          */
 128         if(dirb->mode & DMDIR){
 129                 fprint(2, "mv: %s is a directory, not copied to %s\n",
 130                         fromname, toname);
 131                 return -1;
 132         }
 133         fdf = open(fromname, OREAD);
 134         if(fdf < 0){
 135                 fprint(2, "mv: can't open %s: %r\n", fromname);
 136                 return -1;
 137         }
 138
 139         dirt = dirstat(toname);
 140         if(dirt != nil && (dirt->mode & DMAPPEND))
 141                 hardremove(toname);  /* because create() won't truncate file */
 142         free(dirt);
 143
 144         fdt = create(toname, OWRITE, dirb->mode);
 145         if(fdt < 0){
 146                 fprint(2, "mv: can't create %s: %r\n", toname);
 147                 close(fdf);
 148                 return -1;
 149         }
 150         stat = copy1(fdf, fdt, fromname, toname);
 151         close(fdf);
 152
 153         if(stat >= 0){
 154                 nulldir(&null);
 155                 null.mtime = dirb->mtime;
 156                 null.mode = dirb->mode;
 157                 dirfwstat(fdt, &null);  /* ignore errors; e.g. user none always fails */
 158                 if(remove(fromname) < 0){
 159                         fprint(2, "mv: can't remove %s: %r\n", fromname);
 160                         stat = -1;
 161                 }
 162         }
 163         close(fdt);
 164         return stat;
 165 }
 166
 167 int
 168 copy1(int fdf, int fdt, char *from, char *to)
 169 {
 170         char buf[8192];
 171         long n, n1;
 172
 173         while ((n = read(fdf, buf, sizeof buf)) > 0) {
 174                 n1 = write(fdt, buf, n);
 175                 if(n1 != n){
 176                         fprint(2, "mv: error writing %s: %r\n", to);
 177                         return -1;
 178                 }
 179         }
 180         if(n < 0){
 181                 fprint(2, "mv: error reading %s: %r\n", from);
 182                 return -1;
 183         }
 184         return 0;
 185 }
 186
 187 void
 188 split(char *name, char **pdir, char **pelem)
 189 {
 190         char *s;
 191
 192         s = utfrrune(name, '/');
 193         if(s){
 194                 *s = 0;
 195                 *pelem = s+1;
 196                 *pdir = name;
 197         }else if(strcmp(name, "..") == 0){
 198                 *pdir = "..";
 199                 *pelem = ".";
 200         }else{
 201                 *pdir = ".";
 202                 *pelem = name;
 203         }
 204 }
 205
 206 int
 207 samefile(char *a, char *b)
 208 {
 209         Dir *da, *db;
 210         int ret;
 211
 212         if(strcmp(a, b) == 0)
 213                 return 1;
 214         da = dirstat(a);
 215         db = dirstat(b);
 216         ret = (da != nil && db != nil &&
 217                 da->qid.type==db->qid.type &&
 218                 da->qid.path==db->qid.path &&
 219                 da->qid.vers==db->qid.vers &&
 220                 da->dev==db->dev &&
 221                 da->type==db->type);
 222         free(da);
 223         free(db);
 224         return ret;
 225 }
 226
 227 void
 228 hardremove(char *a)
 229 {
 230         if(remove(a) == -1){
 231                 fprint(2, "mv: can't remove %s: %r\n", a);
 232                 exits("mv");
 233         }
 234         while(remove(a) != -1)
 235                 ;
 236 }