Merge branch 'lukeshu/flash-file'HEADmain

1 files changed, 128 insertions, 0 deletions

diff --git a/flashimg/cpu_main/flash_static.c b/flashimg/cpu_main/flash_static.c
new file mode 100644
index 0000000..4529ab2
--- /dev/null
+++ b/flashimg/cpu_main/flash_static.c
@@ -0,0 +1,128 @@
+/* flashimg/cpu_main/flash_static.c - Serve static files from flash over 9P
+ *
+ * Copyright (C) 2024-2025  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+#include <hardware/flash.h>
+
+#include <libmisc/assert.h>
+
+#include "flashio.h"
+
+#include "flash_static.h"
+
+LO_IMPLEMENTATION_C(lib9p_srv_file, struct flash_static_file, flash_static_file);
+LO_IMPLEMENTATION_STATIC(lib9p_srv_fio, struct flash_static_file, flash_static_fio);
+
+/******************************************************************************/
+
+#ifdef NDEBUG
+#define flash_static_assert(self) ((void)0)
+#else
+static void flash_static_assert(struct flash_static_file *self) {
+	assert(self);
+	assert(self->io);
+	assert(XIP_BASE <= (uintptr_t)self->data_start);
+	assert((uintptr_t)self->data_start <= (uintptr_t)self->data_end);
+	assert((uintptr_t)self->data_end <= XIP_BASE+PICO_FLASH_SIZE_BYTES);
+}
+#endif
+
+static inline size_t flash_static_size(struct flash_static_file *file) {
+	flash_static_assert(file);
+
+	return (size_t)((uintptr_t)file->data_end - (uintptr_t)file->data_start);
+}
+
+/******************************************************************************/
+
+void flash_static_file_free(struct flash_static_file *self) {
+	flash_static_assert(self);
+}
+struct lib9p_qid flash_static_file_qid(struct flash_static_file *self) {
+	flash_static_assert(self);
+
+	return (struct lib9p_qid){
+		.type = LIB9P_QT_FILE,
+		.vers = 1,
+		.path = self->c.pathnum,
+	};
+}
+error flash_static_file_stat(struct flash_static_file *self, struct lib9p_srv_ctx *ctx, struct lib9p_srv_stat *out) {
+	flash_static_assert(self);
+	assert(ctx);
+	assert(out);
+
+	*out = ((struct lib9p_srv_stat){
+		.qid                 = flash_static_file_qid(self),
+		.mode                = self->c.perm & 0444,
+		.atime_sec           = self->c.atime,
+		.mtime_sec           = self->c.mtime,
+		.size                = (uint64_t)flash_static_size(self),
+		.name                = lib9p_str(self->c.name),
+		.owner_uid           = { .name = lib9p_str(self->c.u_name), .num = self->c.u_num },
+		.owner_gid           = { .name = lib9p_str(self->c.g_name), .num = self->c.g_num },
+		.last_modifier_uid   = { .name = lib9p_str(self->c.m_name), .num = self->c.m_num },
+		.extension           = lib9p_str(NULL),
+	});
+	return ERROR_NULL;
+}
+error flash_static_file_wstat(struct flash_static_file *self, struct lib9p_srv_ctx *ctx, struct lib9p_srv_stat) {
+	flash_static_assert(self);
+	assert(ctx);
+
+	return error_new(E_POSIX_EROFS, "read-only part of filesystem");
+}
+error flash_static_file_remove(struct flash_static_file *self, struct lib9p_srv_ctx *ctx) {
+	flash_static_assert(self);
+	assert(ctx);
+
+	return error_new(E_POSIX_EROFS, "read-only part of filesystem");
+}
+
+LIB9P_SRV_NOTDIR(, struct flash_static_file, flash_static_file);
+
+lib9p_srv_fio_or_error flash_static_file_fopen(struct flash_static_file *self, struct lib9p_srv_ctx *ctx, bool rd, bool wr, bool trunc) {
+	flash_static_assert(self);
+	assert(ctx);
+	assert(rd);
+	assert(!wr);
+	assert(!trunc);
+	return ERROR_NEW_VAL(lib9p_srv_fio, LO_BOX(lib9p_srv_fio, self));
+}
+
+/******************************************************************************/
+
+static struct lib9p_qid flash_static_fio_ioqid(struct flash_static_file *self) {
+	return flash_static_file_qid(self);
+}
+static void flash_static_fio_iofree(struct flash_static_file *self) {
+	flash_static_assert(self);
+}
+static uint32_t flash_static_fio_iounit(struct flash_static_file *self) {
+	flash_static_assert(self);
+	return 0;
+}
+static error flash_static_fio_pread(struct flash_static_file *self, struct lib9p_srv_ctx *ctx, lo_interface io_writer dst, uint64_t byte_offset, uint32_t byte_count) {
+	flash_static_assert(self);
+	assert(ctx);
+
+	size_t data_size = flash_static_size(self);
+	if (byte_offset > (uint64_t)data_size)
+		return error_new(E_POSIX_EINVAL, "offset is past end-of-file length");
+
+	if (byte_count > data_size - byte_offset)
+		byte_count = data_size - byte_offset;
+
+	return flashio_pread_to(self->io, dst, ((uintptr_t)self->data_start - XIP_BASE) + byte_offset, byte_count).err;
+}
+static uint32_t_or_error flash_static_fio_pwrite(struct flash_static_file *self, struct lib9p_srv_ctx *ctx,
+                                                 const void *LM_UNUSED(buf),
+                                                 uint32_t LM_UNUSED(byte_count),
+                                                 uint64_t LM_UNUSED(byte_offset)) {
+	flash_static_assert(self);
+	assert(ctx);
+
+	return ERROR_NEW_ERR(uint32_t, error_new(E_POSIX_EROFS, "read-only part of filesystem"));
+}