grammar for the grammar and lexing and parsing of a new language lbp

1 files changed, 258 insertions, 0 deletions

diff --git a/demos/sample-files/lbp-skeleton.c b/demos/sample-files/lbp-skeleton.c
new file mode 100644
index 0000000..ae0a17f
--- /dev/null
+++ b/demos/sample-files/lbp-skeleton.c
@@ -0,0 +1,258 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <ctype.h>
+
+// TODO: lr parser is bad for debugging
+
+#define INPUT_CAP 4096
+#define ARENA_CAP 4096
+
+#define ARENA_IMPLEMENTATION
+#include "util/arena.h"
+
+static char buf[ARENA_CAP];
+static struct arena_ctx global_arena;
+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;
+}
+
+// other things here
+#include "util/list.h"
+static inline struct list_head *list_new_head(struct list_head *head, struct list_head *new)
+{
+    if(head) list_add(new, head);
+    return new;
+}
+
+#define list_new_head(head, new) (intptr_t)list_new_head((struct list_head *)head, (struct list_head *)new)
+
+// generated
+#include "bin/lbp.h"
+#include "bin/lbp.c"
+
+#include "util/dict.h"
+static struct dict types_dict;
+static struct string_token types_strings[] = {
+    {"int", T_INT},
+    {"enum", T_ENUM},
+    {"struct", T_STRUCT},
+    {"function", ST_FUNCTION},
+    {"big", ST_BIG},
+    {"little", ST_LITTLE},
+    {"native", ST_NATIVE},
+};
+static size_t ntypes_strings = sizeof(types_strings)/sizeof(*types_strings);
+static uint8_t dict_lowercase_char_to_bit[256] = {
+    ['a'] = 2,  ['b'] = 3,  ['c'] = 4,  ['d'] = 5,  ['e'] = 6,  ['f'] = 7,
+    ['g'] = 8,  ['h'] = 9,  ['i'] = 10, ['j'] = 11, ['k'] = 12, ['l'] = 13,
+    ['m'] = 14, ['n'] = 15, ['o'] = 16, ['p'] = 17, ['q'] = 18, ['r'] = 19,
+    ['s'] = 20, ['t'] = 21, ['u'] = 22, ['v'] = 23, ['w'] = 24, ['x'] = 25,
+    ['y'] = 26, ['z'] = 27, [ 0 ] = 1,  [' '] = 1
+};
+
+
+#include "parts/toklist.h"
+struct token {
+    symbol s;
+    intptr_t v;
+};
+
+#include "util/queue.h"
+QUEUE_GENERATE(tokbuf, struct token, 16)
+
+symbol token_sym(struct token *t) { return t->s; }
+intptr_t token_val(struct token *t) { return t->v; }
+
+static void print_token(struct token *t);
+static char *next_token(char *str);
+
+static char *input;
+
+struct token *toklist_eat()
+{
+    static struct token t;
+    tokbuf_dequeue(&t); // err not checked
+    if(tokbuf_empty()) input = next_token(input);
+    return &t;
+}
+
+struct token *toklist_peek() {
+    static struct token t;
+    tokbuf_peek(&t);   // err not checked
+    return &t;
+}
+
+// #define _LR_PARSER_DEBUG
+#include "lr-parser.c"
+
+int main(void)
+{
+    static char input_buf[INPUT_CAP];
+    if(fread(input_buf, INPUT_CAP, 1, stdin) == INPUT_CAP) {
+        fprintf(stderr, "INPUT_CAP reached\n");
+        return 1;
+    }
+
+    global_arena = ARENA_CTX_INIT(buf, ARENA_CAP);
+
+    types_dict = DICT_INIT(types_strings, ntypes_strings, dict_lowercase_char_to_bit);
+    dict_compile(&types_dict);
+
+    input = next_token(input_buf);
+
+    // while(1) {
+    //     struct token *tok = toklist_eat();
+    //     print_token(tok);
+    //     if(token_sym(tok) == END_INPUT) break;
+    // } return 0;
+
+    intptr_t value;
+    if(lr_parser(&value)) {
+        fprintf(stderr, input);
+        return 1;
+    }
+
+    fprintf(stderr, "OUTPUT: %jd\n", value);
+
+    dict_free(&types_dict);
+    return 0;
+}
+
+static void print_token(struct token *tok)
+{
+    printf("%s\n", symbol_to_str[token_sym(tok)]);
+    if(token_sym(tok) == IDEN || token_sym(tok) == ATOM) printf("  %s\n", (char *)token_val(tok));
+}
+
+// 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(!str) return sub;
+
+    if(sub_end+1 > sizeof(sub)) return NULL;
+
+    sub[sub_end] = '\0';
+    return memcpy(sub, str, sub_end);
+}
+
+static inline size_t tillch(char *str, size_t len, char ch)
+{
+    for(size_t i = 0; i < len; i++) if(str[i] == ch) return i;
+    return len;
+}
+
+// LEXER
+
+static inline int issep(char c)
+{
+    return isspace(c) || c == '\0' || c == '/' || c == ',' || 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 *typelist_tokenize(char *str)
+{
+    size_t off = 0;
+    while(!issep(str[off]) && str[off] != '-') off++;
+
+    if(off > 0) {
+        int s = dict_check(&types_dict, substring(str, off));
+        if(s < 0) {
+            fprintf(stderr, "ERROR: Unknown type or subtype %s\n", substring(NULL, 0));
+            return NULL;
+        }
+
+        tokbuf_enqueue(&(struct token){.s = s, .v = s});
+    }
+
+    str += off;
+
+    switch(str[0]) {
+    case '-': return typelist_tokenize(str+1);
+    case '(':
+        while((str = next_token(str)))
+            if(*(str-1)== ')') { // not really
+                if(str[0] == '-') return typelist_tokenize(str+1);
+                else return str;
+            }
+        return NULL;
+    default: return str;
+    }
+}
+
+static char *next_token(char *str)
+{
+    if(!str) return str;
+
+    struct token tok = {0};
+    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 = COMMA; break;
+            case ';': tok.s = SEMICOL; break;
+            case '.': tok.s = DOT; break;
+            case '(': tok.s = LPAREN; break;
+            case ')': tok.s = RPAREN; break;
+            case '{': tok.s = LBRACE; break;
+            case '}': tok.s = RBRACE; break;
+            case '/':
+                tok.s = TYPELIST_START; tokbuf_enqueue(&tok);
+                if(!(str = typelist_tokenize(str+off))) goto fail;
+                tok.s = TYPELIST_END; tokbuf_enqueue(&tok);
+                return str;
+            default: break;
+            }
+        } else if(c0 >= '0' && c0 <= '9') { // num
+            tok.s = NUM;
+            tok.v = (intptr_t)atoi(substring(str, off)); // not really
+        } else { // iden or atom (possibly with fields)
+            int hasfield = 0;
+            size_t sub_off;
+
+            do {
+                sub_off = tillch(str + 1, off - 1, ':') + 1;
+                if(hasfield)
+                    tokbuf_enqueue(&(struct token){.s = COLON, .v = 0});
+
+                tokbuf_enqueue(&(struct token){.s = (!hasfield && str[0] == ':') ? ATOM : IDEN,
+                                               .v = (intptr_t)strdup(substring(str+hasfield, sub_off-hasfield))});
+            } while(hasfield = 1, str += sub_off, off -= sub_off, off > 0);
+
+            return str;
+        }
+    }
+
+    tokbuf_enqueue(&tok);
+    return str+off;
+
+fail:
+    tokbuf_enqueue(&(struct token){.s = END_INPUT});
+    return NULL;
+}