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resolve_includes.c
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| // Given the string `input`, replaces every instance of `#include "file"` with the contents | |
| // of `file` (relative to `include_dir`). The returned string aliases `input` if no includes were found, | |
| // otherwise it's a new copy with the same lifetime as `arena`. | |
| String8 file_resolve_includes(Arena *arena, String8 input, String8 include_dir) | |
| { | |
| String8 output = {}; | |
| String8 include_str = str8("#include"); | |
| Temp scratch = scratch_begin(&arena, 1); | |
| // locate all include directives | |
| struct Include { | |
| usz pos; | |
| usz len; // length of the include directive, up to the last '"' | |
| String8 file; | |
| }; | |
| struct Include includes[256] = {}; | |
| u64 n_includes = 0; | |
| u64 pos = 0; | |
| while (pos < input.size - include_str.size) { | |
| const char *include_pos = strstr(cstr(input) + pos, cstr(include_str)); | |
| if (!include_pos) | |
| break; | |
| if (n_includes == countof(includes)) { | |
| ERR_TAG("Files", "Too many #include directives."); | |
| return output; | |
| } | |
| struct Include inc; | |
| inc.pos = (u8 *)include_pos - input.str; | |
| // parse file name | |
| pos = inc.pos + include_str.size; | |
| u8 c; | |
| do { | |
| c = input.str[pos++]; | |
| } while (pos < input.size && (c == ' ' || c == '\t')); | |
| if (c != '"') { | |
| ERR_TAG("Files", "Error resolving includes: expected '\"' after #include, found %c (at pos %zu).\n", c, pos - 1); | |
| u8 code[50] = {}; | |
| memcpy(code, input.str + pos - 20, countof(code)); | |
| ERR_TAG("Files", "Code around pos:\n%s\n", code); | |
| assert(false); | |
| return output; | |
| } | |
| u8 *included_file_start = input.str + pos; | |
| usz included_file_size = 0; | |
| b8 found_closing_quote = false; | |
| while (pos < input.size) { | |
| c = input.str[pos++]; | |
| if (c == '"') { | |
| found_closing_quote = true; | |
| break; | |
| } | |
| ++included_file_size; | |
| } | |
| if (!found_closing_quote) { | |
| ERR_TAG("Files", "Error resolving includes: unterminated string after #include directive.\n"); | |
| assert(false); | |
| return output; | |
| } | |
| if (included_file_size == 0) { | |
| ERR_TAG("Files", "Error resolving includes: empty string in #include directive.\n"); | |
| assert(false); | |
| return output; | |
| } | |
| String8 included_file = str8_from_buf(scratch.arena, included_file_start, included_file_size); | |
| inc.file = push_str8f(scratch.arena, "%s/%s", cstr(include_dir), cstr(included_file)); | |
| inc.len = pos - inc.pos; | |
| includes[n_includes++] = inc; | |
| } | |
| // Copy content into output | |
| if (n_includes == 0) { | |
| output = input; | |
| return output; | |
| } | |
| u64 output_tot_bytes = input.size; | |
| for (u64 i = 0; i < n_includes; ++i) { | |
| FILE *f = fopen(cstr(includes[i].file), "r"); | |
| if (!f) { | |
| ERR_TAG("Files", "Failed to open included file %s", cstr(includes[i].file)); | |
| return output; | |
| } | |
| output_tot_bytes += file_size(f); | |
| output_tot_bytes -= includes[i].len; | |
| fclose(f); | |
| } | |
| output.size = output_tot_bytes; | |
| output.str = arena_push_array_nozero(u8, arena, output.size + 1); | |
| output.str[output.size] = 0; | |
| usz input_pos = 0; | |
| usz output_pos = 0; | |
| for (u64 inc_idx = 0; inc_idx < n_includes; ++inc_idx) { | |
| struct Include *inc = &includes[inc_idx]; | |
| assert(inc->pos >= input_pos); | |
| usz input_len = inc->pos - input_pos; | |
| if (input_len > 0) { | |
| memcpy(output.str + output_pos, input.str + input_pos, input_len); | |
| input_pos += input_len; | |
| output_pos += input_len; | |
| } | |
| u64 arena_pre_pos = arena_pos(scratch.arena); | |
| String8 inc_file_content = file_read_to_string(scratch.arena, inc->file); | |
| if (inc_file_content.size > 0) { | |
| memcpy(output.str + output_pos, inc_file_content.str, inc_file_content.size); | |
| input_pos += inc->len; | |
| output_pos += inc_file_content.size; | |
| } | |
| arena_pop_to(scratch.arena, arena_pre_pos); | |
| assert(output_pos < output.size); | |
| } | |
| usz rem = input.size - input_pos; | |
| assert(rem == output.size - output_pos); | |
| if (rem > 0) | |
| memcpy(output.str + output_pos, input.str + input_pos, rem); | |
| return output; | |
| } |
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