FEAT: VFS overhaul

src/fs/sysfs.c

@@ -0,0 +1,181 @@
+#include "vfs.h"
+#include "../sys/kernel_subsystem.h"
+#include "memory_manager.h"
+#include "core/kutils.h"
+
+typedef struct {
+    kernel_subsystem_t *sub;
+    subsystem_file_t *file;
+    int offset;
+} sysfs_handle_t;
+
+static void* sysfs_open(void *fs_private, const char *path, const char *mode) {
+    if (path[0] == '/') path++;
+    if (path[0] == '\0') return NULL;
+
+    kernel_subsystem_t *sub = NULL;
+    int last_slash = -1;
+    for (int j = 0; path[j]; j++) if (path[j] == '/') last_slash = j;
+
+    if (last_slash != -1) {
+        char prefix[64];
+        k_memcpy(prefix, path, last_slash);
+        prefix[last_slash] = 0;
+        sub = subsystem_get_by_name(prefix);
+        
+        if (sub) {
+            const char *filename = path + last_slash + 1;
+            for (int j = 0; j < sub->file_count; j++) {
+                if (k_strcmp(sub->files[j].name, filename) == 0) {
+                    sysfs_handle_t *h = (sysfs_handle_t*)kmalloc(sizeof(sysfs_handle_t));
+                    h->sub = sub;
+                    h->file = &sub->files[j];
+                    h->offset = 0;
+                    return h;
+                }
+            }
+        }
+    }
+
+    return NULL;
+}
+
+static void sysfs_close(void *fs_private, void *handle) {
+    if (handle) kfree(handle);
+}
+
+static int sysfs_read(void *fs_private, void *handle, void *buf, int size) {
+    sysfs_handle_t *h = (sysfs_handle_t*)handle;
+    if (!h || !h->file || !h->file->read) return -1;
+
+    int bytes = h->file->read((char*)buf, size, h->offset);
+    if (bytes > 0) h->offset += bytes;
+    return bytes;
+}
+
+static int sysfs_write(void *fs_private, void *handle, const void *buf, int size) {
+    sysfs_handle_t *h = (sysfs_handle_t*)handle;
+    if (!h || !h->file || !h->file->write) return -1;
+
+    int bytes = h->file->write((const char*)buf, size, h->offset);
+    if (bytes > 0) h->offset += bytes;
+    return bytes;
+}
+
+static int sysfs_readdir(void *fs_private, const char *path, vfs_dirent_t *entries, int max) {
+    if (path[0] == '/') path++;
+    
+    kernel_subsystem_t *exact_sub = subsystem_get_by_name(path);
+    int out = 0;
+
+    if (exact_sub) {
+        for (int i = 0; i < exact_sub->file_count && out < max; i++) {
+            k_strcpy(entries[out].name, exact_sub->files[i].name);
+            entries[out].is_directory = 0;
+            entries[out].size = 0;
+            out++;
+        }
+    }
+
+    int count = subsystem_get_count();
+    int path_len = k_strlen(path);
+
+    for (int i = 0; i < count && out < max; i++) {
+        kernel_subsystem_t *s = subsystem_get_by_index(i);
+        if (path_len == 0 || (k_strlen(s->name) > path_len && k_strncmp(s->name, path, path_len) == 0 && s->name[path_len] == '/')) {
+            const char *sub_path = s->name + (path_len ? path_len + 1 : 0);
+            char comp[64];
+            int j = 0;
+            while (sub_path[j] && sub_path[j] != '/' && j < 63) {
+                comp[j] = sub_path[j];
+                j++;
+            }
+            comp[j] = 0;
+
+            if (comp[0] == '\0') continue;
+
+            bool found = false;
+            for (int k = 0; k < out; k++) {
+                if (k_strcmp(entries[k].name, comp) == 0) {
+                    found = true;
+                    break;
+                }
+            }
+            if (!found) {
+                k_strcpy(entries[out].name, comp);
+                entries[out].is_directory = 1;
+                entries[out].size = 0;
+                out++;
+            }
+        }
+    }
+    return out;
+}
+
+static bool sysfs_exists(void *fs_private, const char *path) {
+    if (path[0] == '/') path++;
+    if (path[0] == '\0') return true;
+
+    if (subsystem_get_by_name(path)) return true;
+
+    // File check
+    int last_slash = -1;
+    for (int j = 0; path[j]; j++) if (path[j] == '/') last_slash = j;
+    if (last_slash != -1) {
+        char prefix[64];
+        k_memcpy(prefix, path, last_slash);
+        prefix[last_slash] = 0;
+        kernel_subsystem_t *sub = subsystem_get_by_name(prefix);
+        if (sub) {
+            const char *filename = path + last_slash + 1;
+            for (int j = 0; j < sub->file_count; j++) {
+                if (k_strcmp(sub->files[j].name, filename) == 0) return true;
+            }
+        }
+    }
+
+    int count = subsystem_get_count();
+    int path_len = k_strlen(path);
+    for (int i = 0; i < count; i++) {
+        kernel_subsystem_t *s = subsystem_get_by_index(i);
+        if (k_strlen(s->name) > path_len && k_strncmp(s->name, path, path_len) == 0 && s->name[path_len] == '/') return true;
+    }
+
+    return false;
+}
+
+static bool sysfs_is_dir(void *fs_private, const char *path) {
+    if (path[0] == '/') path++;
+    if (path[0] == '\0') return true;
+
+    int last_slash = -1;
+    for (int j = 0; path[j]; j++) if (path[j] == '/') last_slash = j;
+    if (last_slash != -1) {
+        char prefix[64];
+        k_memcpy(prefix, path, last_slash);
+        prefix[last_slash] = 0;
+        kernel_subsystem_t *sub = subsystem_get_by_name(prefix);
+        if (sub) {
+            const char *filename = path + last_slash + 1;
+            for (int j = 0; j < sub->file_count; j++) {
+                if (k_strcmp(sub->files[j].name, filename) == 0) return false;
+            }
+        }
+    }
+
+    return sysfs_exists(fs_private, path);
+}
+
+vfs_fs_ops_t sysfs_ops = {
+    .open = sysfs_open,
+    .close = sysfs_close,
+    .read = sysfs_read,
+    .write = sysfs_write,
+    .readdir = sysfs_readdir,
+    .exists = sysfs_exists,
+    .is_dir = sysfs_is_dir
+};
+
+vfs_fs_ops_t* sysfs_get_ops(void) {
+    return &sysfs_ops;
+}