push

usr/lib/libcervus/dirent/dirent.c

@@ -0,0 +1,59 @@
+#include <dirent.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <sys/syscall.h>
+
+typedef struct {
+    uint64_t d_ino;
+    uint8_t  d_type;
+    char     d_name[256];
+} __kernel_dirent_t;
+
+struct __cervus_DIR {
+    int fd;
+    struct dirent buf;
+};
+
+DIR *opendir(const char *path)
+{
+    int fd = open(path, O_RDONLY | O_DIRECTORY, 0);
+    if (fd < 0) return NULL;
+    DIR *d = (DIR *)malloc(sizeof(DIR));
+    if (!d) { close(fd); return NULL; }
+    d->fd = fd;
+    return d;
+}
+
+struct dirent *readdir(DIR *dirp)
+{
+    if (!dirp) return NULL;
+    __kernel_dirent_t kde;
+    int r = (int)syscall2(SYS_READDIR, dirp->fd, &kde);
+    if (r != 0) return NULL;
+    dirp->buf.d_ino  = kde.d_ino;
+    dirp->buf.d_type = kde.d_type;
+    size_t nl = strlen(kde.d_name);
+    if (nl >= sizeof(dirp->buf.d_name)) nl = sizeof(dirp->buf.d_name) - 1;
+    memcpy(dirp->buf.d_name, kde.d_name, nl);
+    dirp->buf.d_name[nl] = '\0';
+    return &dirp->buf;
+}
+
+int closedir(DIR *dirp)
+{
+    if (!dirp) return -1;
+    int fd = dirp->fd;
+    free(dirp);
+    return close(fd);
+}
+
+void rewinddir(DIR *dirp)
+{
+    if (!dirp) return;
+    lseek(dirp->fd, 0, SEEK_SET);
+}
+
+int dirfd(DIR *dirp) { return dirp ? dirp->fd : -1; }