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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#define ARENA_IMPLEMENTATION
#include "util/arena.h"
static char buf[1024];
static struct arena_ctx global_arena = ARENA_CTX_INIT(buf, sizeof(buf));
static void *xalloc(size_t sz) {
void *addr = arena_allocate(&global_arena, sz);
if(!addr) {
fprintf(stderr, "ERROR: Arena empty\n"); exit(1);
}
return addr;
}
// generated
#include "bin/gram.h"
#include "bin/gram.c"
#include "parts/toklist.h"
struct token {
symbol s;
intptr_t v;
} tok;
static char *next_token(char *str);
symbol token_sym(struct token *t) { return t->s; }
intptr_t token_val(struct token *t) { return t->v; }
static char *input = (char []){
"-left B;"
"-right C;"
"-left D;"
""
"A: B {a}"
" | C N {d}."
};
struct token *toklist_eat()
{
static struct token t;
t = tok;
input = next_token(input);
return &t;
}
struct token *toklist_peek() { return &tok; }
#include "lr-parser.c"
int main(void)
{
input = next_token(input);
intptr_t value;
if(lr_parser(&value)) {
return 1;
}
printf("OUTPUT: %jd\n", value);
return 0;
}
// STR UTIL
#define strdup(...) _strdup(__VA_ARGS__)
static inline char *_strdup(char *str)
{
return memcpy(xalloc(strlen(str) + 1), str, strlen(str)+1);
}
static inline char *substring(char *str, size_t sub_end)
{
static char sub[128];
if(sub_end+1 > sizeof(sub)) return NULL;
sub[sub_end] = '\0';
return memcpy(sub, str, sub_end);
}
// LEXER
static inline int issep(char c)
{
return isspace(c) || c == '\0' || c == ':' || c == '|' || c == ';' || c == '.' || c == '-' || c == '{';
}
static inline int tillsep(char *str)
{
size_t i = 0;
while(!issep(str[i++]));
return i-1;
}
static char *next_token(char *str)
{
if(!str) return str;
size_t off = 0;
char c0 = str[0];
if(c0 == '\0') tok.s = END_INPUT;
if(isspace(c0)) return next_token(str+1);
else {
off = tillsep(str);
if(off == 0) { // sep
switch(str[off++]) {
case ':': tok.s = COLON; break;
case '|': tok.s = PIPE; break;
case ';': tok.s = SEMICOL; break;
case '.': tok.s = DOT; break;
case '-':
off = tillsep(++str);
char *s = substring(str, off);
if(strcmp(s, "left") == 0) tok.s = D_LEFT;
else if(strcmp(s, "right") == 0) tok.s = D_RIGHT;
else if(strcmp(s, "terminal") == 0) tok.s = D_TERMINAL;
else if(strcmp(s, "nonterminal") == 0) tok.s = D_NONTERM;
else { fprintf(stderr, "ERROR: Unknown directive '-%s'\n", s); goto fail; }
break;
case '{':
for(int c = 1; c != 0; off++)
if(str[off] == '\0') { fprintf(stderr, "ERROR: No closing '{'\n"); goto fail; }
else if(str[off] == '{') c++;
else if(str[off] == '}') c--;
tok.s = ACTION;
tok.v = (intptr_t)strdup(substring(str, off));
break;
}
} else if(isalpha(c0)) { // iden or named symbol
tok.s = IDEN;
tok.v = (intptr_t)strdup(substring(str, off));
} else if(c0 >= '0' && c0 <= '9') { // num
tok.s = NUM;
tok.v = (intptr_t)atoi(substring(str, off));
}
}
return str+off;
fail:
tok.s = END_INPUT;
return NULL;
}
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