From 29086b1d12a2c28cffdbfbf0b3990a7bd75506b9 Mon Sep 17 00:00:00 2001 From: Jari Vetoniemi Date: Thu, 20 Apr 2017 16:49:35 +0300 Subject: work in progress --- src/fspec/lexer.rl | 616 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 616 insertions(+) create mode 100644 src/fspec/lexer.rl (limited to 'src/fspec/lexer.rl') diff --git a/src/fspec/lexer.rl b/src/fspec/lexer.rl new file mode 100644 index 0000000..81390e2 --- /dev/null +++ b/src/fspec/lexer.rl @@ -0,0 +1,616 @@ +#include "ragel/ragel.h" +#include +#include +#include "bcode-internal.h" + +#include +#include +#include +#include + +#define PLACEHOLDER 0xDEADBEEF +#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0])) + +typedef uint8_t fspec_strsz; + +struct membuf { + struct fspec_mem mem; + fspec_off written; +}; + +static void +membuf_bounds_check(const struct membuf *buf, const fspec_off nmemb) +{ + assert(buf); + + if (buf->mem.len < nmemb || buf->written > buf->mem.len - nmemb) + errx(EXIT_FAILURE, "%s: %" PRI_FSPEC_OFF " bytes exceeds the maximum storage size of %zu bytes", __func__, buf->written + nmemb, buf->mem.len); +} + +static void +membuf_terminate(struct membuf *buf, const void *data, const fspec_off data_sz) +{ + membuf_bounds_check(buf, data_sz); + memcpy((char*)buf->mem.data + buf->written, data, data_sz); +} + +static void +membuf_replace(struct membuf *buf, const fspec_off off, const void *data, const fspec_off data_sz) +{ + assert(buf->mem.len >= data_sz && off <= buf->mem.len - data_sz); + memcpy((char*)buf->mem.data + off, data, data_sz); +} + +static void +membuf_append_at(struct membuf *buf, const fspec_off off, const void *data, const fspec_off data_sz) +{ + assert(off <= buf->written); + membuf_bounds_check(buf, data_sz); + const size_t rest = buf->written - off; + memmove((char*)buf->mem.data + off + data_sz, (char*)buf->mem.data + off, rest); + membuf_replace(buf, off, data, data_sz); + buf->written += data_sz; + assert(buf->written <= buf->mem.len); +} + +static void +membuf_append(struct membuf *buf, const void *data, const fspec_off data_sz) +{ + membuf_append_at(buf, buf->written, data, data_sz); +} + +struct varbuf { + struct membuf buf; + fspec_off offset; +}; + +static inline void +varbuf_begin(struct varbuf *var) +{ + assert(var); + var->offset = var->buf.written; + assert(var->offset <= var->buf.mem.len); +} + +static void +varbuf_reset(struct varbuf *var) +{ + assert(var); + var->offset = var->buf.written = 0; +} + +static inline void +varbuf_remove_last(struct varbuf *var) +{ + assert(var); + assert(var->buf.written >= var->offset); + const fspec_off size = var->buf.written - var->offset; + assert(var->buf.written >= size); + var->buf.written -= size; + assert(var->buf.written <= var->buf.mem.len); +} + +enum section { + SECTION_DATA, + SECTION_CODE, + SECTION_LAST, +}; + +struct codebuf { + struct membuf buf; + const void *decl[FSPEC_DECLARATION_LAST], *end[SECTION_LAST], *strings; + fspec_var declarations; +}; + +static void +codebuf_append(struct codebuf *code, const enum section section, const void *data, const fspec_off data_sz) +{ + assert(code->end[section]); + const fspec_off off = (char*)code->end[section] - (char*)code->buf.mem.data; + membuf_append_at(&code->buf, off, data, data_sz); + + for (enum section s = section; s < ARRAY_SIZE(code->end); ++s) { + code->end[s] = (char*)code->end[s] + data_sz; + assert((char*)code->end[s] <= (char*)code->buf.mem.data + code->buf.mem.len); + } + + if (section == SECTION_DATA) { + for (enum fspec_declaration d = 0; d < ARRAY_SIZE(code->decl); ++d) { + code->decl[d] = (code->decl[d] ? (char*)code->decl[d] + data_sz : NULL); + assert((char*)code->decl[d] <= (char*)code->buf.mem.data + code->buf.mem.len); + } + } + + assert(code->end[SECTION_DATA] <= code->end[SECTION_CODE]); + assert((char*)code->end[SECTION_CODE] == (char*)code->buf.mem.data + code->buf.written); +} + +static void +codebuf_append_op(struct codebuf *code, const enum fspec_op op) +{ + codebuf_append(code, SECTION_CODE, &op, sizeof(op)); +} + +static uint8_t +arg_sizeof(const enum fspec_arg type) +{ + switch (type) { + case FSPEC_ARG_DAT: + case FSPEC_ARG_OFF: + case FSPEC_ARG_STR: + return sizeof(fspec_off); + + case FSPEC_ARG_NUM: + return sizeof(fspec_num); + + case FSPEC_ARG_VAR: + return sizeof(fspec_var); + + case FSPEC_ARG_EOF: + break; + + case FSPEC_ARG_LAST: + errx(EXIT_FAILURE, "%s: unexpected argument type %u", __func__, type); + } + + return 0; +} + +static void +codebuf_append_arg(struct codebuf *code, const enum fspec_arg type, const void *v) +{ + assert(code); + codebuf_append_op(code, FSPEC_OP_ARG); + codebuf_append(code, SECTION_CODE, &type, sizeof(type)); + codebuf_append(code, SECTION_CODE, v, arg_sizeof(type)); +} + +static void +codebuf_replace_arg(struct codebuf *code, const enum fspec_arg *arg, const enum fspec_arg type, const void *v) +{ + assert(code && arg); + assert(*arg == type); + const fspec_off off = ((char*)arg + 1) - (char*)code->buf.mem.data; + membuf_replace(&code->buf, off, v, arg_sizeof(type)); +} + +static bool +get_string_offset(const void *start, const void *end, const void *str, const fspec_strsz str_sz, void const **out_off) +{ + assert(out_off); + + while (start < end) { + fspec_strsz len; + memcpy(&len, start, sizeof(len)); + if (len == str_sz && !memcmp((char*)start + sizeof(len), str, len)) { + *out_off = start; + return true; + } + start = (char*)start + sizeof(len) + len + 1; + } + + return false; +} + +static void +codebuf_append_arg_cstr(struct codebuf *code, const void *str, const fspec_strsz str_sz) +{ + const void *ptr; + if (!get_string_offset(code->strings, code->end[SECTION_DATA], str, str_sz, &ptr)) { + ptr = code->end[SECTION_DATA]; + codebuf_append(code, SECTION_DATA, &str_sz, sizeof(str_sz)); + codebuf_append(code, SECTION_DATA, str, str_sz); + codebuf_append(code, SECTION_DATA, (char[]){ 0 }, 1); + } + + const fspec_off off = (char*)ptr - (char*)code->buf.mem.data; + codebuf_append_arg(code, FSPEC_ARG_STR, &off); +} + +static const enum fspec_op* +get_named_op(const enum fspec_op *start, const void *end, const void *data, const enum fspec_op op, const uint8_t nth, const void *name, const fspec_strsz name_sz, fspec_var *out_id) +{ + fspec_var id = 0; + if ((void*)start < end && *start == FSPEC_OP_DECLARATION) + id = fspec_arg_get_num(fspec_op_get_arg(start, end, 2, 1<decl[FSPEC_DECLARATION_STRUCT] : code->end[SECTION_DATA]); + return get_named_op(start, code->end[SECTION_CODE], code->buf.mem.data, FSPEC_OP_DECLARATION, 4, str->data, str->len, out_id); +} + +static bool +codebuf_append_arg_var(struct codebuf *code, const bool member, const struct fspec_mem *var) +{ + fspec_var id = -1; + if (!get_declaration(code, member, var, &id)) + return false; + + codebuf_append_arg(code, FSPEC_ARG_VAR, &id); + return true; +} + +static void +codebuf_append_declaration(struct codebuf *code, const enum fspec_declaration decl) +{ + code->decl[decl] = code->end[SECTION_CODE]; + codebuf_append_op(code, FSPEC_OP_DECLARATION); + codebuf_append_arg(code, FSPEC_ARG_NUM, (fspec_num[]){ decl }); + codebuf_append_arg(code, FSPEC_ARG_NUM, (fspec_num[]){ code->declarations++ }); + codebuf_append_arg(code, FSPEC_ARG_OFF, (fspec_off[]){ PLACEHOLDER }); +} + +enum stack_type { + STACK_STR, + STACK_NUM, +}; + +struct stack { + union { + struct fspec_mem str; + uint64_t num; + }; + enum stack_type type; +}; + +static const char* +stack_type_to_str(const enum stack_type type) +{ + switch (type) { + case STACK_STR: return "str"; + case STACK_NUM: return "num"; + }; + return "unknown"; +} + +static void +stack_check_type(const struct stack *stack, const enum stack_type type) +{ + assert(stack); + + if (stack->type != type) + errx(EXIT_FAILURE, "tried to get '%s' from stack, but the last pushed type was '%s'", stack_type_to_str(type), stack_type_to_str(stack->type)); +} + +static const struct fspec_mem* +stack_get_str(const struct stack *stack) +{ + stack_check_type(stack, STACK_STR); + return &stack->str; +} + +static uint64_t +stack_get_num(const struct stack *stack) +{ + stack_check_type(stack, STACK_NUM); + return stack->num; +} + +struct state { + struct ragel ragel; + struct stack stack; + struct codebuf out; + struct varbuf var; +}; + +static void +state_stack_num(struct state *state, const uint8_t base) +{ + assert(state); + membuf_terminate(&state->var.buf, (char[]){ 0 }, 1); + const char *str = (char*)state->var.buf.mem.data + state->var.offset; + state->stack.type = STACK_NUM; + state->stack.num = strtoll(str + (base == 16 && *str == 'x'), NULL, base); + varbuf_remove_last(&state->var); +} + +static void +state_append_arg_var(struct state *state, const bool member, const struct fspec_mem *str) +{ + assert(state && str); + + if (!codebuf_append_arg_var(&state->out, member, str)) + ragel_throw_error(&state->ragel, "'%s' undeclared", (char*)str->data); +} + +static void +state_append_declaration(struct state *state, const enum fspec_declaration decl, const struct fspec_mem *str) +{ + assert(state && str); + + if (get_declaration(&state->out, (decl == FSPEC_DECLARATION_MEMBER), str, NULL)) + ragel_throw_error(&state->ragel, "'%s' redeclared", (char*)str->data); + + codebuf_append_declaration(&state->out, decl); + codebuf_append_arg_cstr(&state->out, str->data, str->len); +} + +static void +state_finish_declaration(struct state *state, const enum fspec_declaration decl) +{ + assert(state && state->out.decl[decl]); + const char *end = state->out.end[SECTION_CODE]; + const fspec_off off = end - (char*)state->out.decl[decl]; + codebuf_replace_arg(&state->out, fspec_op_get_arg(state->out.decl[decl], end, 3, 1<out.decl[decl] = NULL; +} + +%%{ + machine fspec_lexer; + variable p state.ragel.p; + variable pe state.ragel.pe; + variable eof state.ragel.eof; + write data noerror nofinal; + + action arg_eof { + codebuf_append_arg(&state.out, FSPEC_ARG_EOF, NULL); + } + + action arg_num { + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ stack_get_num(&state.stack) }); + } + + action arg_str { + const struct fspec_mem *str = stack_get_str(&state.stack); + codebuf_append_arg_cstr(&state.out, str->data, str->len); + } + + action arg_var { + state_append_arg_var(&state, true, stack_get_str(&state.stack)); + } + + action filter { + codebuf_append_op(&state.out, FSPEC_OP_FILTER); + } + + action goto { + codebuf_append_op(&state.out, FSPEC_OP_GOTO); + state_append_arg_var(&state, false, stack_get_str(&state.stack)); + } + + action vnul { + codebuf_append_op(&state.out, FSPEC_OP_VISUAL); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ FSPEC_VISUAL_NUL }); + } + + action vdec { + codebuf_append_op(&state.out, FSPEC_OP_VISUAL); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ FSPEC_VISUAL_DEC }); + } + + action vhex { + codebuf_append_op(&state.out, FSPEC_OP_VISUAL); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ FSPEC_VISUAL_HEX }); + } + + action vstr { + codebuf_append_op(&state.out, FSPEC_OP_VISUAL); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ FSPEC_VISUAL_STR }); + } + + action r8 { + codebuf_append_op(&state.out, FSPEC_OP_READ); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ 8 }); + } + + action r16 { + codebuf_append_op(&state.out, FSPEC_OP_READ); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ 16 }); + } + + action r32 { + codebuf_append_op(&state.out, FSPEC_OP_READ); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ 32 }); + } + + action r64 { + codebuf_append_op(&state.out, FSPEC_OP_READ); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ 64 }); + } + + action member_end { + state_finish_declaration(&state, FSPEC_DECLARATION_MEMBER); + } + + action member_start { + state_append_declaration(&state, FSPEC_DECLARATION_MEMBER, stack_get_str(&state.stack)); + } + + action struct_end { + state_finish_declaration(&state, FSPEC_DECLARATION_STRUCT); + } + + action struct_start { + state_append_declaration(&state, FSPEC_DECLARATION_STRUCT, stack_get_str(&state.stack)); + } + + action stack_oct { + state_stack_num(&state, 8); + } + + action stack_hex { + state_stack_num(&state, 16); + } + + action stack_dec { + state_stack_num(&state, 10); + } + + action stack_str { + membuf_terminate(&state.var.buf, (char[]){ 0 }, 1); + state.stack.type = STACK_STR; + state.stack.str = state.var.buf.mem; + state.stack.str.len = state.var.buf.written; + } + + action store_esc_num { + const fspec_num v = stack_get_num(&state.stack); + assert(v <= 255); + const uint8_t u8 = v; + membuf_append(&state.var.buf, &u8, sizeof(u8)); + } + + action store_esc { + const struct { const char e, v; } map[] = { + { .e = 'a', .v = '\a' }, + { .e = 'b', .v = '\b' }, + { .e = 'f', .v = '\f' }, + { .e = 'n', .v = '\n' }, + { .e = 'r', .v = '\r' }, + { .e = 't', .v = '\t' }, + { .e = 'v', .v = '\v' }, + { .e = '\\', .v = '\\' }, + { .e = '\'', .v = '\'' }, + { .e = '\"', .v = '"' }, + { .e = 'e', .v = 0x1B }, + }; + + for (size_t i = 0; i < ARRAY_SIZE(map); ++i) { + if (*state.ragel.p != map[i].e) + continue; + + membuf_append(&state.var.buf, &map[i].v, sizeof(map[i].v)); + break; + } + } + + action store { + membuf_append(&state.var.buf, state.ragel.p, 1); + } + + action begin_num { + varbuf_begin(&state.var); + } + + action begin_str { + varbuf_reset(&state.var); + } + + action type_err { + ragel_throw_error(&state.ragel, "unknown type name"); + } + + action visual_err { + ragel_throw_error(&state.ragel, "unknown visualization"); + } + + action syntax_err { + ragel_throw_error(&state.ragel, "malformed input (machine failed here or in next expression)"); + } + + action line { + ragel_advance_line(&state.ragel); + } + + # Semantic + quote = ['"]; + newline = '\n'; + esc = [abfnrtv\\'"e]; + esc_chr = '\\'; + esc_hex = 'x' <: xdigit{2}; + hex = '0' <: esc_hex; + oct = [0-7]{1,3}; + dec = [\-+]? <: (([1-9] <: digit*) | '0'); + valid = ^cntrl; + comment = '//' <: valid* :>> newline; + type = ('u8' | 's8') %r8 | ('u16' | 's16') %r16 | ('u32' | 's32') %r32 | ('u64' | 's32') %r64; + visual = 'nul' %vnul | 'dec' %vdec | 'hex' %vhex | 'str' %vstr; + reserved = 'struct' | type | visual; + name = ((alpha | '_') <: (alnum | '_')*) - reserved; + + # Stack + stack_name = name >begin_str $store %stack_str; + stack_hex = hex >begin_num $store %stack_hex; + stack_dec = dec >begin_num $store %stack_dec; + stack_oct = oct >begin_num $store %stack_oct; + stack_esc_hex = esc_hex >begin_num $store %stack_hex; + stack_esc = esc_chr <: ((stack_esc_hex | stack_oct) %store_esc_num | esc %~store_esc); + stack_str = quote <: ((stack_esc? <: print? $store) - zlen)* >begin_str %stack_str :>> quote; + stack_num = stack_dec | stack_hex; + + # Catchers + catch_struct = 'struct ' <: stack_name; + catch_type = (catch_struct %goto | type) $!type_err; + catch_args = stack_num %arg_num | stack_str %arg_str | stack_name %arg_var; + catch_array = '[' <: (catch_args | '$' %arg_eof) :>> ']'; + catch_filter = ' | ' %filter <: stack_name %arg_str :>> ('(' <: catch_args? <: (', ' <: catch_args)* :>> ')')?; + catch_visual = ' ' <: visual $!visual_err; + + # Abstract + member = stack_name %member_start :> ': ' <: (catch_type <: catch_array* catch_filter* catch_visual?) :>> ';' %member_end; + struct = catch_struct %struct_start :>> ' {' <: (space | comment | member)* :>> '};' %struct_end; + line = valid* :>> newline %line; + main := ((space | comment | struct)* & line*) $!syntax_err; +}%% + +bool +fspec_lexer_parse(struct fspec_lexer *lexer, const char *name) +{ + int cs; + %% write init; + + (void)fspec_lexer_en_main; + assert(lexer); + assert(lexer->ops.read); + assert(lexer->mem.input.data && lexer->mem.input.len); + assert(lexer->mem.output.data && lexer->mem.output.len); + assert(lexer->mem.input.len <= (size_t)~0 && "input storage size exceeds size_t range"); + assert(lexer->mem.output.len <= (fspec_off)~0 && "output storage size exceeds fspec_off range"); + + char var[256]; + struct state state = { + .ragel.name = name, + .ragel.lineno = 1, + .var.buf.mem = { .data = var, .len = sizeof(var) }, + .out.buf.mem = lexer->mem.output, + }; + + static const fspec_num version = 0; + state.out.end[SECTION_CODE] = state.out.end[SECTION_DATA] = state.out.buf.mem.data; + codebuf_append_op(&state.out, FSPEC_OP_HEADER); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, &version); + codebuf_append_arg(&state.out, FSPEC_ARG_NUM, (fspec_num[]){ PLACEHOLDER }); + codebuf_append_arg(&state.out, FSPEC_ARG_DAT, (fspec_off[]){ PLACEHOLDER }); + state.out.end[SECTION_DATA] = state.out.end[SECTION_CODE]; + state.out.strings = state.out.end[SECTION_DATA]; + + struct fspec_mem input = lexer->mem.input; + for (bool eof = false; !state.ragel.error && !eof;) { + const size_t bytes = lexer->ops.read(lexer, input.data, 1, input.len); + const struct ragel_mem rl = { .data = input.data, .end = (char*)input.data + bytes }; + ragel_feed_input(&state.ragel, (eof = (bytes < input.len)), &rl); + %% write exec; + } + + { + const void *end = state.out.end[SECTION_CODE]; + codebuf_replace_arg(&state.out, fspec_op_get_arg(state.out.buf.mem.data, end, 2, 1<mem.output.len = state.out.buf.written; + return !state.ragel.error; +} -- cgit v1.2.3