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- /* Copyright (C) 2014-2015 Ben Kurtovic <ben.kurtovic@gmail.com>
- Released under the terms of the MIT License. See LICENSE for details. */
-
- #include <stdlib.h>
-
- #include "assembler.h"
- #include "assembler/directives.h"
- #include "assembler/errors.h"
- #include "assembler/io.h"
- #include "assembler/parse_util.h"
- #include "assembler/preprocessor.h"
- #include "assembler/state.h"
- #include "logging.h"
- #include "rom.h"
- #include "util.h"
-
- #define IS_LABEL(line) (line->data[line->length - 1] == ':')
-
- /* Sentinel values for overlap table */
- const ASMLine header_sentinel, bounds_sentinel;
-
- /*
- Add a given line, representing a label, to the symbol table.
-
- Return NULL on success and an ErrorInfo object on failure (in the case of
- duplicate labels).
- */
- static ErrorInfo* add_label_to_table(
- ASMSymbolTable *symtable, const ASMLine *line, size_t offset)
- {
- char *symbol = strndup(line->data, line->length - 1);
- if (!symbol)
- OUT_OF_MEMORY()
-
- const ASMSymbol *current = asm_symtable_find(symtable, symbol);
- if (current) {
- ErrorInfo *ei = error_info_create(line, ET_LAYOUT, ED_LYT_DUPE_LABELS);
- error_info_append(ei, current->line);
- return ei;
- }
-
- ASMSymbol *label = malloc(sizeof(ASMSymbol));
- if (!label)
- OUT_OF_MEMORY()
-
- label->offset = offset;
- label->symbol = symbol;
- label->line = line;
- asm_symtable_insert(symtable, label);
- return NULL;
- }
-
- /*
- Parse data encoded in a line into an ASMData object.
-
- On success, return NULL and store the instruction in *data_ptr. On failure,
- return an ErrorInfo object; *data_ptr is not modified.
- */
- static ErrorInfo* parse_data(
- const ASMLine *line, ASMData **data_ptr, size_t offset)
- {
- // TODO
-
- return error_info_create(line, ET_PARSER, ED_PARSE_SYNTAX);
- }
-
- /*
- Parse an instruction encoded in a line into an ASMInstruction object.
-
- On success, return NULL and store the instruction in *inst_ptr. On failure,
- return an ErrorInfo object; *inst_ptr is not modified.
- */
- static ErrorInfo* parse_instruction(
- const ASMLine *line, ASMInstruction **inst_ptr, size_t offset)
- {
- // TODO
-
- return error_info_create(line, ET_PARSER, ED_PARSE_SYNTAX);
- }
-
- /*
- Check if the given location overlaps with any existing objects.
-
- On success, return NULL and add the location to the overlap table.
- On failure, return an ErrorInfo object.
- */
- static ErrorInfo* check_layout(
- const ASMLine **overlap_table, size_t size, const ASMLocation *loc,
- const ASMLine *line, const ASMLine *origin)
- {
- const ASMLine *clash = NULL;
-
- if (loc->offset + loc->length >= size) {
- clash = &bounds_sentinel;
- } else {
- for (size_t i = 0; i < loc->length; i++) {
- if (overlap_table[loc->offset + i]) {
- clash = overlap_table[loc->offset + i];
- break;
- }
- }
- }
-
- if (clash) {
- ErrorInfo *ei = error_info_create(line, ET_LAYOUT,
- (clash == &header_sentinel) ? ED_LYT_OVERLAP_HEAD :
- (clash == &bounds_sentinel) ? ED_LYT_BOUNDS : ED_LYT_OVERLAP);
-
- if (origin)
- error_info_append(ei, origin);
- if (clash != &header_sentinel && clash != &bounds_sentinel)
- error_info_append(ei, clash);
- return ei;
- }
-
- for (size_t i = 0; i < loc->length; i++)
- overlap_table[loc->offset + i] = line;
- return NULL;
- }
-
- /*
- Tokenize ASMLines into ASMInstructions.
-
- NULL is returned on success and an ErrorInfo object is returned on failure.
- state->instructions, state->data, and state->symtable may or may not be
- modified regardless of success.
- */
- static ErrorInfo* tokenize(AssemblerState *state)
- {
- size_t size = state->rom_size ? state->rom_size : ROM_SIZE_MAX;
- const ASMLine **overlap_table = calloc(size, sizeof(const ASMLine*));
- if (!overlap_table)
- OUT_OF_MEMORY()
-
- ErrorInfo *ei = NULL;
- ASMInstruction dummy_inst = {.next = NULL}, *inst, *prev_inst = &dummy_inst;
- ASMData dummy_data = {.next = NULL}, *data, *prev_data = &dummy_data;
- const ASMLine *line = state->lines, *origin = NULL;
- size_t offset = 0;
-
- for (size_t i = 0; i < HEADER_SIZE; i++)
- overlap_table[state->header.offset + i] = &header_sentinel;
-
- while (line) {
- if (IS_LABEL(line)) {
- if ((ei = add_label_to_table(state->symtable, line, offset)))
- goto cleanup;
- }
- else if (IS_LOCAL_DIRECTIVE(line)) {
- if (IS_DIRECTIVE(line, DIR_ORIGIN)) {
- if (!DIRECTIVE_HAS_ARG(line, DIR_ORIGIN)) {
- ei = error_info_create(line, ET_PREPROC, ED_PP_NO_ARG);
- goto cleanup;
- }
-
- uint32_t arg;
- if (!dparse_uint32_t(&arg, line, DIR_ORIGIN)) {
- ei = error_info_create(line, ET_PREPROC, ED_PP_BAD_ARG);
- goto cleanup;
- }
-
- offset = arg;
- origin = line;
- }
- else {
- if ((ei = parse_data(line, &data, offset)))
- goto cleanup;
-
- offset += data->loc.length;
- prev_data->next = data;
- prev_data = data;
-
- if ((ei = check_layout(overlap_table, size, &data->loc, line, origin)))
- goto cleanup;
- }
- }
- else {
- if ((ei = parse_instruction(line, &inst, offset)))
- goto cleanup;
-
- offset += inst->loc.length;
- prev_inst->next = inst;
- prev_inst = inst;
-
- if ((ei = check_layout(overlap_table, size, &inst->loc, line, origin)))
- goto cleanup;
- }
- line = line->next;
- }
-
- cleanup:
- state->instructions = dummy_inst.next;
- state->data = dummy_data.next;
- free(overlap_table);
- return ei;
- }
-
- /*
- Resolve default placeholder values in assembler state, such as ROM size.
-
- On success, no new heap objects are allocated. On error, an ErrorInfo
- object is returned.
- */
- static ErrorInfo* resolve_defaults(AssemblerState *state)
- {
- if (!state->rom_size) {
- state->rom_size = ROM_SIZE_MIN;
-
- // TODO: use highest instruction too
-
- if (state->header.rom_size != INVALID_SIZE_CODE) {
- size_t decl_size = size_code_to_bytes(state->header.rom_size);
- if (decl_size > state->rom_size)
- state->rom_size = decl_size;
- }
- }
-
- if (state->header.rom_size == INVALID_SIZE_CODE)
- state->header.rom_size = size_bytes_to_code(state->rom_size);
-
- return NULL;
- }
-
- /*
- Resolve symbol placeholders in instructions such as jumps and branches.
-
- On success, no new heap objects are allocated. On error, an ErrorInfo
- object is returned.
- */
- static ErrorInfo* resolve_symbols(AssemblerState *state)
- {
- // TODO
-
- (void) state;
- return NULL;
- }
-
- /*
- Convert finalized ASMInstructions and ASMData into a binary data block.
-
- This function should never fail.
- */
- static void serialize_binary(AssemblerState *state, uint8_t *binary)
- {
- // TODO
-
- for (size_t i = 0; i < state->rom_size; i++)
- binary[i] = 'X';
- }
-
- /*
- Assemble the z80 source code in the source code buffer into binary data.
-
- If successful, return the size of the assembled binary data and change
- *binary_ptr to point to the assembled ROM data buffer. *binary_ptr must be
- free()'d when finished.
-
- If an error occurred, return 0 and update *ei_ptr to point to an ErrorInfo
- object which can be shown to the user with error_info_print(). The
- ErrorInfo object must be destroyed with error_info_destroy() when finished.
-
- In either case, only one of *binary_ptr and *ei_ptr is modified.
- */
- size_t assemble(const LineBuffer *source, uint8_t **binary_ptr, ErrorInfo **ei_ptr)
- {
- AssemblerState state;
- ErrorInfo *error_info;
- size_t retval = 0;
-
- state_init(&state);
-
- if ((error_info = preprocess(&state, source)))
- goto error;
-
- asm_symtable_init(&state.symtable);
-
- #ifdef DEBUG_MODE
- asm_lines_print(state.lines);
- #endif
-
- if ((error_info = tokenize(&state)))
- goto error;
-
- if ((error_info = resolve_defaults(&state)))
- goto error;
-
- if ((error_info = resolve_symbols(&state)))
- goto error;
-
- uint8_t *binary = malloc(sizeof(uint8_t) * state.rom_size);
- if (!binary)
- OUT_OF_MEMORY()
-
- serialize_binary(&state, binary);
- *binary_ptr = binary;
- retval = state.rom_size;
- goto cleanup;
-
- error:
- *ei_ptr = error_info;
-
- cleanup:
- state_free(&state);
- return retval;
- }
-
- /*
- Assemble the z80 source code at the input path into a binary file.
-
- Return true if the operation was a success and false if it was a failure.
- Errors are printed to STDOUT; if the operation was successful then nothing
- is printed.
- */
- bool assemble_file(const char *src_path, const char *dst_path)
- {
- LineBuffer *source = read_source_file(src_path, true);
- if (!source)
- return false;
-
- uint8_t *binary;
- ErrorInfo *error_info;
- size_t size = assemble(source, &binary, &error_info);
- line_buffer_free(source);
-
- if (!size) {
- error_info_print(error_info, stderr);
- error_info_destroy(error_info);
- return false;
- }
-
- bool success = write_binary_file(dst_path, binary, size);
- free(binary);
- return success;
- }
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