ref: 1d891d163e814a93ee5346cf05b4fac297bf3a5c
dir: /sys/src/ape/lib/ap/plan9/opendir.c/
#include "lib.h" #include <stdlib.h> #include <sys/stat.h> #include <dirent.h> #include <unistd.h> #include <errno.h> #include <string.h> #include "sys9.h" #include "dir.h" #define DBLOCKSIZE 20 DIR * opendir(const char *filename) { int f, n; DIR *d; char *s; n = strlen(filename); if(n > 0 && filename[n-1] != '/'){ s = malloc(n+2); if(s == NULL) goto Nomem; memcpy(s, filename, n); s[n++] = '/'; s[n] = 0; } else s = filename; f = open(s, O_RDONLY); if(s != filename) free(s); if(f < 0){ _syserrno(); return NULL; } _fdinfo[f].flags |= FD_CLOEXEC; d = (DIR *)malloc(sizeof(DIR) + DBLOCKSIZE*sizeof(struct dirent)); if(d == NULL){ Nomem: errno = ENOMEM; return NULL; } d->dd_buf = (char *)d + sizeof(DIR); d->dd_fd = f; d->dd_loc = 0; d->dd_size = 0; d->dirs = NULL; d->dirsize = 0; d->dirloc = 0; return d; } int closedir(DIR *d) { int fd; if(d == NULL){ errno = EBADF; return -1; } fd = d->dd_fd; free(d->dirs); free(d); return close(fd); } void rewinddir(DIR *d) { if(d == NULL) return; d->dd_loc = 0; d->dd_size = 0; d->dirsize = 0; d->dirloc = 0; free(d->dirs); d->dirs = NULL; if(_SEEK(d->dd_fd, 0, 0) < 0){ _syserrno(); return; } } struct dirent * readdir(DIR *d) { int i; struct dirent *dr; Dir *dirs, *dir; if(d == NULL){ errno = EBADF; return NULL; } if(d->dd_loc >= d->dd_size){ if(d->dirloc >= d->dirsize){ free(d->dirs); d->dirs = NULL; d->dirsize = _dirread(d->dd_fd, &d->dirs); d->dirloc = 0; } if(d->dirsize < 0) { /* malloc or read failed in _dirread? */ free(d->dirs); d->dirs = NULL; } if(d->dirs == NULL) return NULL; dr = (struct dirent *)d->dd_buf; dirs = d->dirs; for(i=0; i<DBLOCKSIZE && d->dirloc < d->dirsize; i++){ dir = &dirs[d->dirloc++]; strncpy(dr[i].d_name, dir->name, MAXNAMLEN); dr[i].d_name[MAXNAMLEN] = 0; _dirtostat(&dr[i].d_stat, dir, NULL); } d->dd_loc = 0; d->dd_size = i*sizeof(struct dirent); } dr = (struct dirent*)(d->dd_buf+d->dd_loc); d->dd_loc += sizeof(struct dirent); return dr; }