projects / micropolis / blame
| Commit | Line | Data |
|---|---|---|
| 6a5fa4e0 MG |
1 | /* |
| 2 | * opendir.c -- | |
| 3 | * | |
| 4 | * This file provides dirent-style directory-reading procedures | |
| 5 | * for V7 Unix systems that don't have such procedures. The | |
| 6 | * origin of this code is unclear, but it seems to have come | |
| 7 | * originally from Larry Wall. | |
| 8 | * | |
| 9 | */ | |
| 10 | ||
| 11 | #include <tclint.h> | |
| 12 | #include <tclunix.h> | |
| 13 | ||
| 14 | #undef DIRSIZ | |
| 15 | #define DIRSIZ(dp) \ | |
| 16 | ((sizeof (struct dirent) - (MAXNAMLEN+1)) + (((dp)->d_namlen+1 + 3) &~ 3)) | |
| 17 | ||
| 18 | /* | |
| 19 | * open a directory. | |
| 20 | */ | |
| 21 | DIR * | |
| 22 | opendir(name) | |
| 23 | char *name; | |
| 24 | { | |
| 25 | register DIR *dirp; | |
| 26 | register int fd; | |
| 27 | char *myname; | |
| 28 | ||
| 29 | myname = ((*name == '\0') ? "." : name); | |
| 30 | if ((fd = open(myname, 0, 0)) == -1) | |
| 31 | return NULL; | |
| 32 | if ((dirp = (DIR *)ckalloc(sizeof(DIR))) == NULL) { | |
| 33 | close (fd); | |
| 34 | return NULL; | |
| 35 | } | |
| 36 | dirp->dd_fd = fd; | |
| 37 | dirp->dd_loc = 0; | |
| 38 | return dirp; | |
| 39 | } | |
| 40 | ||
| 41 | /* | |
| 42 | * read an old style directory entry and present it as a new one | |
| 43 | */ | |
| 44 | #ifndef pyr | |
| 45 | #define ODIRSIZ 14 | |
| 46 | ||
| 47 | struct olddirect { | |
| 48 | ino_t od_ino; | |
| 49 | char od_name[ODIRSIZ]; | |
| 50 | }; | |
| 51 | #else /* a Pyramid in the ATT universe */ | |
| 52 | #define ODIRSIZ 248 | |
| 53 | ||
| 54 | struct olddirect { | |
| 55 | long od_ino; | |
| 56 | short od_fill1, od_fill2; | |
| 57 | char od_name[ODIRSIZ]; | |
| 58 | }; | |
| 59 | #endif | |
| 60 | ||
| 61 | /* | |
| 62 | * get next entry in a directory. | |
| 63 | */ | |
| 64 | struct dirent * | |
| 65 | readdir(dirp) | |
| 66 | register DIR *dirp; | |
| 67 | { | |
| 68 | register struct olddirect *dp; | |
| 69 | static struct dirent dir; | |
| 70 | ||
| 71 | for (;;) { | |
| 72 | if (dirp->dd_loc == 0) { | |
| 73 | dirp->dd_size = read(dirp->dd_fd, dirp->dd_buf, | |
| 74 | DIRBLKSIZ); | |
| 75 | if (dirp->dd_size <= 0) | |
| 76 | return NULL; | |
| 77 | } | |
| 78 | if (dirp->dd_loc >= dirp->dd_size) { | |
| 79 | dirp->dd_loc = 0; | |
| 80 | continue; | |
| 81 | } | |
| 82 | dp = (struct olddirect *)(dirp->dd_buf + dirp->dd_loc); | |
| 83 | dirp->dd_loc += sizeof(struct olddirect); | |
| 84 | if (dp->od_ino == 0) | |
| 85 | continue; | |
| 86 | dir.d_ino = dp->od_ino; | |
| 87 | strncpy(dir.d_name, dp->od_name, ODIRSIZ); | |
| 88 | dir.d_name[ODIRSIZ] = '\0'; /* insure null termination */ | |
| 89 | dir.d_namlen = strlen(dir.d_name); | |
| 90 | dir.d_reclen = DIRSIZ(&dir); | |
| 91 | return (&dir); | |
| 92 | } | |
| 93 | } | |
| 94 | ||
| 95 | /* | |
| 96 | * close a directory. | |
| 97 | */ | |
| 98 | void | |
| 99 | closedir(dirp) | |
| 100 | register DIR *dirp; | |
| 101 | { | |
| 102 | close(dirp->dd_fd); | |
| 103 | dirp->dd_fd = -1; | |
| 104 | dirp->dd_loc = 0; | |
| 105 | ckfree((char *) dirp); | |
| 106 | } |