feat: add fs target

.github/workflows/ci.yml

@@ -68,6 +68,7 @@ jobs:
       - name: Download loader
         run: gh release download --repo hermit-os/loader --pattern hermit-loader-${{ matrix.arch }}
       - run: cargo xtask ci c --arch ${{ matrix.arch }} --buildtype ${{ matrix.buildtype }} --target hello_world qemu ${{ matrix.flags }}
+      - run: cargo xtask ci c --arch ${{ matrix.arch }} --buildtype ${{ matrix.buildtype }} --target fs qemu ${{ matrix.flags }}
       - run: cargo xtask ci c --arch ${{ matrix.arch }} --buildtype ${{ matrix.buildtype }} --target http_server qemu ${{ matrix.flags }} --netdev virtio-net-pci
       - run: cargo xtask ci c --arch ${{ matrix.arch }} --buildtype ${{ matrix.buildtype }} --target http_server_poll qemu ${{ matrix.flags }} --netdev virtio-net-pci
       - run: cargo xtask ci c --arch ${{ matrix.arch }} --buildtype ${{ matrix.buildtype }} --target math qemu ${{ matrix.flags }}

meson.build

@@ -40,6 +40,7 @@ else
     hermit = []
 endif
 
+executable('fs', 'src/fs.c', link_whole: hermit)
 executable('hello_world', 'src/hello_world.c', link_whole: hermit)
 executable('http_server', 'src/http_server.c', link_whole: hermit)
 executable('http_server_poll', 'src/http_server_poll.c', link_whole: hermit)

src/fs.c

@@ -0,0 +1,218 @@
+// NOLINTNEXTLINE(bugprone-reserved-identifier)
+#define _GNU_SOURCE
+// NOLINTNEXTLINE(bugprone-reserved-identifier)
+#define _LARGEFILE64_SOURCE
+#include "print_assert.h"
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+static int create_dir(const char *path) {
+    fprintf(stderr, "create_dir(\"%s\")\n", path);
+
+    mode_t mode = S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH;
+
+    fprintf(stderr, "mkdir(\"%s\")\n", path);
+    int mkdir_status = mkdir(path, mode);
+    if (mkdir_status == -1) {
+        perror("mkdir() failed");
+        return -1;
+    }
+
+    fprintf(stderr, "stat(\"%s\")\n", path);
+    struct stat buffer;
+    int stat_status = stat(path, &buffer);
+    if (stat_status == -1) {
+        perror("stat() failed");
+        return -1;
+    }
+
+    print_assert((buffer.st_mode & mode) == mode);
+
+    fputc('\n', stderr);
+    return 0;
+}
+
+static int remove_dir(const char *path) {
+    fprintf(stderr, "remove_dir(\"%s\")\n", path);
+
+    fprintf(stderr, "rmdir(\"%s\")\n", path);
+    int rmdir_status = rmdir(path);
+    if (rmdir_status == -1) {
+        perror("rmdir() failed");
+        return -1;
+    }
+
+    fputc('\n', stderr);
+    return 0;
+}
+
+static int create_files(const char *dir_path, size_t file_count) {
+    fprintf(stderr, "create_files(\"%s\", %zu)\n", dir_path, file_count);
+
+    mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
+    int oflag = O_WRONLY | O_CREAT | O_TRUNC;
+
+    for (size_t i = 0; i < file_count; ++i) {
+        char file_path[256];
+        int written =
+            snprintf(file_path, sizeof(file_path), "%s/file_%zu", dir_path, i);
+        if (written < 0) {
+            perror("snprintf() failed");
+            return -1;
+        }
+        if ((size_t)written + 1 > sizeof(file_path)) {
+            fprintf(stderr, "snprintf() failed: buffer too small");
+            return -1;
+        }
+
+        fprintf(stderr, "open(\"%s\")\n", file_path);
+        int fd = open(file_path, oflag, mode);
+        if (fd == -1) {
+            perror("open() failed");
+            return -1;
+        }
+
+        fprintf(stderr, "fstat(%i)\n", fd);
+        struct stat buffer;
+        int fstat_status = fstat(fd, &buffer);
+        if (fstat_status == -1) {
+            perror("fstat() failed");
+            return -1;
+        }
+
+        print_assert((buffer.st_mode & mode) == mode);
+
+        fprintf(stderr, "close(%i)\n", fd);
+        int closed = close(5);
+        if (closed == -1) {
+            perror("close() failed");
+            return -1;
+        }
+    }
+
+    fputc('\n', stderr);
+    return 0;
+}
+
+static int unlink_files(const char *dir_path, size_t file_count) {
+    fprintf(stderr, "unlink_files(\"%s\", %zu)\n", dir_path, file_count);
+
+    for (size_t i = 0; i < file_count; ++i) {
+        char file_path[256];
+        int written =
+            snprintf(file_path, sizeof(file_path), "%s/file_%zu", dir_path, i);
+        if (written < 0) {
+            perror("snprintf() failed");
+            return -1;
+        }
+        if ((size_t)written + 1 > sizeof(file_path)) {
+            fprintf(stderr, "snprintf() failed: buffer too small");
+            return -1;
+        }
+
+        fprintf(stderr, "unlink(\"%s\")\n", file_path);
+        int fd = unlink(file_path);
+        if (fd == -1) {
+            perror("unlink() failed");
+            return -1;
+        }
+    }
+
+    fputc('\n', stderr);
+    return 0;
+}
+
+struct linux_dirent64 {
+    ino64_t d_ino;
+    off64_t d_off;
+    unsigned short d_reclen;
+    unsigned char d_type;
+    char d_name[];
+};
+
+static int print_getdents64(const char *path) {
+    fprintf(stderr, "print_getdents64(\"%s\")\n", path);
+
+    fprintf(stderr, "open(\"%s\")\n", path);
+    int fd = open(path, 0);
+    if (fd == -1) {
+        perror("open() failed");
+        return -1;
+    }
+
+    fprintf(stderr, "getdents64(%i)\n", fd);
+    char buf[512];
+    ssize_t read = getdents64(fd, (void *)buf, sizeof(buf));
+    if (read == -1) {
+        perror("getdents64() failed");
+        return -1;
+    }
+
+    fputc('\n', stderr);
+    for (size_t pos = 0; pos < (size_t)read;) {
+        struct linux_dirent64 *dirent = (struct linux_dirent64 *)(buf + pos);
+
+        fprintf(stderr, "d_ino = %" PRIu64 "\n", dirent->d_ino);
+        fprintf(stderr, "d_off = %" PRId64 "\n", dirent->d_off);
+        fprintf(stderr, "d_reclen = %hu\n", dirent->d_reclen);
+        fprintf(stderr, "d_type = %hhu\n", dirent->d_type);
+        fprintf(stderr, "d_name = %s\n\n", dirent->d_name);
+
+        pos += dirent->d_reclen;
+    }
+
+    fprintf(stderr, "close(%i)\n", fd);
+    int closed = close(fd);
+    if (closed == -1) {
+        perror("close() failed");
+        return -1;
+    }
+
+    fputc('\n', stderr);
+    return 0;
+}
+
+int main(void) {
+#ifdef __hermit__
+    const char *dir_path = "/my-dir";
+#else
+    const char *dir_path = "my-dir";
+#endif
+
+    int file_count = 3;
+
+    int create_dir_status = create_dir(dir_path);
+    if (create_dir_status == -1) {
+        return EXIT_FAILURE;
+    }
+
+    int create_files_status = create_files(dir_path, file_count);
+    if (create_files_status == -1) {
+        return EXIT_FAILURE;
+    }
+
+    int getdents64_status = print_getdents64(dir_path);
+    if (getdents64_status == -1) {
+        return EXIT_FAILURE;
+    }
+
+    int unlink_status = unlink_files(dir_path, file_count);
+    if (unlink_status == -1) {
+        return EXIT_FAILURE;
+    }
+
+    int remove_dir_status = remove_dir(dir_path);
+    if (remove_dir_status == -1) {
+        return EXIT_FAILURE;
+    }
+
+    return EXIT_SUCCESS;
+}