scc/libs/sccf/src/sccf_builder.c

#include <sccf_builder.h>

void sccf_builder_init(sccf_builder_t *builder) {
    builder->aligned = 64;
    sccf_init(&builder->sccf);
    scc_hashtable_init(&builder->str2offset,
                       (scc_hashtable_hash_func_t)scc_strhash32,
                       (scc_hashtable_equal_func_t)scc_strcmp);
    scc_hashtable_init(&builder->str2sym,
                       (scc_hashtable_hash_func_t)scc_strhash32,
                       (scc_hashtable_equal_func_t)scc_strcmp);

    scc_vec_init(builder->strtab);
    scc_vec_init(builder->relocs);
    scc_vec_init(builder->symtab);

    builder->entry_symbol_name = nullptr;

    ///< Push nullptr
    scc_vec_push(builder->strtab, (char)'\0');
    ///< Push nullptr
    scc_vec_push(builder->symtab, (sccf_sym_t){0});
}

usize sccf_builder_add_symbol(sccf_builder_t *builder, const char *name,
                              sccf_sym_t *sym) {
    usize offset = 0;
    offset = (usize)scc_hashtable_get(&builder->str2offset, name);
    const char *key = name;
    if (offset == 0) {
        offset = scc_vec_size(builder->strtab);
        while (*name) {
            scc_vec_push(builder->strtab, *name);
            name++;
        }
        scc_vec_push(builder->strtab, '\0');

        scc_hashtable_set(&builder->str2offset, key, (void *)offset);
    }
    sym->name_offset = offset;

    usize sym_idx = scc_vec_size(builder->symtab);
    offset = (usize)scc_hashtable_get(&builder->str2sym, key);
    if (offset == 0) {
        scc_hashtable_set(&builder->str2sym, key, (void *)sym_idx);
    } else {
        LOG_ERROR("symbol %s already exists", key);
    }
    scc_vec_push(builder->symtab, *sym);
    return sym_idx;
}

usize sccf_builder_get_symbol_idx(sccf_builder_t *builder, const char *name) {
    usize offset = (usize)scc_hashtable_get(&builder->str2sym, name);
    return offset;
}

void sccf_builder_add_reloc(sccf_builder_t *builder, sccf_reloc_t reloc) {
    scc_vec_push(builder->relocs, reloc);
}

void sccf_builder_add_section(sccf_builder_t *builder,
                              sccf_sect_header_t *sect_header,
                              sccf_sect_data_t *sect_data) {
    Assert((usize)(sect_header->size) == scc_vec_size(*sect_data));
    builder->sccf.header.sect_header_num += 1;
    scc_vec_push(builder->sccf.sect_headers, *sect_header);
    scc_vec_push(builder->sccf.sect_datas, *sect_data);
}

const sccf_t *sccf_builder_to_sccf(sccf_builder_t *builder) {
    if (builder->entry_symbol_name == nullptr) {
        builder->sccf.header.entry_point = 0;
    } else {
        sccf_sym_t *sym =
            sccf_builder_get_symbol_unsafe(builder, builder->entry_symbol_name);
        if (sym == nullptr || sym->sccf_sect_type != SCCF_SECT_CODE) {
            LOG_ERROR("entry symbol %s not found");
            builder->sccf.header.entry_point = 0;
        } else {
            builder->sccf.header.entry_point = sym->sccf_sect_offset;
        }
    }

    sccf_sect_header_t sect_header;
    if (scc_vec_size(builder->strtab)) {
        sect_header = (sccf_sect_header_t){
            .name = ".strtab",
            .info = 0,
            .data_size = scc_vec_size(builder->strtab),
            .addralign = 1,
            .size = scc_vec_size(builder->strtab),
            .sccf_sect_type = SCCF_SECT_STRTAB,
        };
        sccf_builder_add_section(builder, &sect_header,
                                 (void *)&builder->strtab);
    }

    if (scc_vec_size(builder->symtab)) {
        sect_header = (sccf_sect_header_t){
            .name = ".symtab",
            .info = 0,
            .data_size = scc_vec_size(builder->symtab),
            .addralign = 1,
            .size = scc_vec_size(builder->symtab),
            .sccf_sect_type = SCCF_SECT_SYMTAB,
        };
        sccf_builder_add_section(builder, &sect_header,
                                 (void *)&builder->symtab);
    }

    if (scc_vec_size(builder->relocs)) {
        sect_header = (sccf_sect_header_t){
            .name = ".relocs",
            .info = 0,
            .data_size = scc_vec_size(builder->relocs),
            .addralign = 1,
            .size = scc_vec_size(builder->relocs),
            .sccf_sect_type = SCCF_SECT_RELOCS,
        };
        sccf_builder_add_section(builder, &sect_header,
                                 (void *)&builder->relocs);
    }
    return &builder->sccf;
}

void sccf_builder_to_buffer(sccf_builder_t *builder, sccf_buffer_t *buffer) {
    Assert(builder != nullptr && buffer != nullptr);
    sccf_write(sccf_builder_to_sccf(builder), buffer);
}

void sccf_builder_to_file(sccf_builder_t *builder, const char *file_path) {
    Assert(builder != nullptr && file_path != nullptr);
    scc_file_t fp = scc_fopen(file_path, SCC_FILE_WRITE);
    if (fp == nullptr) {
        LOG_ERROR("file can't open %s", file_path);
        return;
    }
    sccf_buffer_t buffer;
    scc_vec_init(buffer);
    sccf_builder_to_buffer(builder, &buffer);
    usize write_size =
        scc_fwrite(fp, scc_vec_unsafe_get_data(buffer), scc_vec_size(buffer));
    if (write_size != scc_vec_size(buffer)) {
        LOG_ERROR("file write failed expect write %zu but got %zu",
                  scc_vec_size(buffer), write_size);
    }
    scc_vec_free(buffer);
    scc_fclose(fp);
}