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#include <ctype.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <stdio.h>
#include "lex.h"
#include "typeutils.h"
typedef struct {
char* str;
size_t pos;
} RawLine;
String collect_identifier(RawLine* line) {
String id_buf = make_String(256);
while (line->str[line->pos] == '_' || isalnum(line->str[line->pos])) {
push_to_String(&id_buf, line->str[line->pos++]);
}
return id_buf;
}
TokenVec lex_level(RawLine* line, char until, ExpansionRegionVec* reg_arena);
void expect_char(RawLine* line, char expected) {
if (line->str[line->pos] != expected) exit(42); // TODO: nicer handling
line->pos++;
}
MaybeChunk lex_expansion_chunk(RawLine* line, ExpansionRegionVec* reg_arena, QuotationMode qmode) {
line->pos++; // Consume $
if (line->str[line->pos] == '(') {
if (line->str[line->pos] == '(') {
TokenVec inner_toks = lex_level(line, ')', reg_arena);
expect_char(line, ')');
expect_char(line, ')');
push_to_ExpansionRegionVec(
reg_arena,
(ExpansionRegion){.mode = ARITHM, .tokens = inner_toks}
);
ExpansionRegion* reg_ptr = ®_arena->items[reg_arena->count]; // TODO: maybe have push() return a pointer [in the macro]
return (MaybeChunk){
.some = true,
.value = (Chunk){
.qmode = qmode,
.kind = REGION_EXP,
.as.reg_ptr = reg_ptr
},
};
} else {
TokenVec inner_toks = lex_level(line, ')', reg_arena);
expect_char(line, ')');
push_to_ExpansionRegionVec(
reg_arena,
(ExpansionRegion){.mode = CMD_SUB, .tokens = inner_toks}
);
ExpansionRegion* reg_ptr = ®_arena->items[reg_arena->count];
return (MaybeChunk) {
.some = true,
.value = (Chunk){
.qmode = qmode,
.kind = REGION_EXP,
.as.reg_ptr = reg_ptr,
}
};
}
} else {
String id_name = collect_identifier(line);
if (id_name.count > 0) {
return (MaybeChunk){
.some = true,
.value = (Chunk){
.qmode = qmode,
.kind = VAR_EXP,
.as.varname = inner(id_name),
}
};
}
}
return (MaybeChunk){.some = false};
}
void lex_double_quoted_section(RawLine* line, ChunkVec* coll, ExpansionRegionVec* reg_arena) {
line->pos++;
String accum = make_String(256);
while (line->str[line->pos] != '\"') {
if (line->str[line->pos] == '\0') exit(42);
MaybeChunk exp_chunk = {.some = false};
if (line->str[line->pos] == '$') {
exp_chunk = lex_expansion_chunk(line, reg_arena, DOUBLE_Q);
if (!exp_chunk.some) {
push_to_String(&accum, '$');
}
} else {
push_to_String(&accum, line->str[line->pos++]);
}
// TODO: other special cases beyond $
if (exp_chunk.some) {
if (accum.count > 0) {
push_to_ChunkVec(coll, (Chunk){
.qmode = DOUBLE_Q,
.kind = LITERAL,
.as.literal_str = inner(accum)
});
accum = make_String(256);
}
push_to_ChunkVec(coll, exp_chunk.value);
exp_chunk.some = false;
}
}
line->pos++;
if (accum.count > 0) {
push_to_ChunkVec(coll, (Chunk){
.qmode = DOUBLE_Q,
.kind = LITERAL,
.as.literal_str = inner(accum)
});
}
}
Chunk next_word_unquoted(RawLine* line, ExpansionRegionVec* reg_arena) {
String buf = make_String(256);
for (char c; (c=line->str[line->pos], c != '$' && c != '\0' && c != ' '); line->pos++) {
push_to_String(&buf, c);
}
return (Chunk){.qmode = UN_Q, .kind = LITERAL, .as.literal_str = inner(buf)};
}
Chunk collect_single_quoted_section(RawLine* line) {
line->pos++; // Consume quote mark
String chunk_str = make_String(256);
while (line->str[line->pos] != '\'') {
if (line->str[line->pos] == '\0') exit(42);
push_to_String(&chunk_str, line->str[line->pos++]);
}
line->pos++; // Consume closing quote
return (Chunk){
.qmode = SINGLE_Q,
.kind = LITERAL,
.as.literal_str = inner(chunk_str),
};
}
TokenVec lex_level(RawLine* line, char until, ExpansionRegionVec* reg_arena) {
TokenVec tokens = make_TokenVec(256);
ChunkVec curr_chunks = make_ChunkVec(256);
String word_buf = make_String(256);
while (line->str[line->pos] != until) {
if (line->str[line->pos] == ' ') {
line->pos++;
continue;
}
switch (line->str[line->pos]) {
case '\'':
push_to_ChunkVec(&curr_chunks, collect_single_quoted_section(line));
break;
case '\"':
lex_double_quoted_section(line, &curr_chunks, reg_arena);
break;
case '$':
line->pos++;
MaybeChunk mchunk = lex_expansion_chunk(line, reg_arena, UN_Q);
if (mchunk.some) {
push_to_ChunkVec(&curr_chunks, mchunk.value);
} else {
push_to_String(&word_buf, '$');
}
break;
default:
push_to_String(&word_buf, line->str[line->pos++]);
}
}
line->pos++; // consume until char
if (word_buf.count > 0) {
push_to_ChunkVec(
&curr_chunks,
(Chunk){.qmode = UN_Q, .kind = LITERAL, .as.literal_str = inner(word_buf)}
);
}
if (curr_chunks.count > 0) {
push_to_TokenVec(&tokens, (Token){.kind = TOK_WORD, .as.word = curr_chunks});
}
return tokens;
}
typedef struct {
TokenVec top_tokens;
ExpansionRegionVec reg_arena;
} LexResult;
TokenVec lex(char* input) {
RawLine line = {.str = input, .pos = 0};
ExpansionRegionVec reg_arena = make_ExpansionRegionVec(256);
return lex_level(&line, '\0', ®_arena);
}
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