From baaef414186e60dbb127662d5f4ffab10ebf225e Mon Sep 17 00:00:00 2001
From: Bad Diode <bd@badd10de.dev>
Date: Fri, 8 Oct 2021 11:37:03 +0200
Subject: Add initial tokenizer

---
 Makefile             |   4 +-
 src/bootstrap/main.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 111 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index 8bd5560..0564240 100755
--- a/Makefile
+++ b/Makefile
@@ -34,9 +34,9 @@ else
     CFLAGS += $(RELEASE_CFLAGS)
 endif
 
-main: tools $(BUILD_DIR) $(ROM) $(BIN)
+main: $(BIN)
 
-$(BIN): $(SRC_MAIN) $(WATCH_SRC)
+$(BIN): $(SRC_MAIN) $(WATCH_SRC) $(BUILD_DIR)
 	$(CC) $(CFLAGS) $(LDFLAGS) -o $(BIN) $(SRC_MAIN) $(LDLIBS)
 
 # Create build directory if needed.
diff --git a/src/bootstrap/main.c b/src/bootstrap/main.c
index 861c206..98f313b 100755
--- a/src/bootstrap/main.c
+++ b/src/bootstrap/main.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <ctype.h>
 
 #include "shorthand.h"
 
@@ -40,6 +41,111 @@ read_line(void) {
     return (StringView){.start = (char *)&readline_buf, .n = n};
 }
 
+typedef struct Tokens {
+    StringView *start;
+    size_t n;
+} Tokens;
+
+Tokens
+tokenize(StringView sv) {
+    // NOTE: Not allocating any memory for now, but we are limited by a maximum
+    // number of tokens we can process.
+    #define TOKENS_BUF_SIZE 1024
+    static StringView tokens_buf[TOKENS_BUF_SIZE];
+
+    // Clear buffer.
+    for (size_t i = 0; i < TOKENS_BUF_SIZE; i++) {
+        tokens_buf[i] = (StringView){0};
+    }
+
+    size_t n = 0;
+    size_t token_n = 0;
+    for (size_t i = 0; i < sv.n; i++) {
+        switch (sv.start[i]) {
+            case ' ':
+            case '\f':
+            case '\n':
+            case '\r':
+            case '\t':
+            case '\v': {
+                if (token_n != 0) {
+                    // Push token.
+                    tokens_buf[n++] = (StringView){
+                        .start = &sv.start[i - token_n],
+                        .n = token_n,
+                    };
+                    token_n = 0;
+                }
+                continue;
+            } break;
+            case '(': {
+                if ((i + 1 < sv.n)) {
+                    char next_c = sv.start[i + 1];
+                    if (isspace(next_c)) {
+                        fprintf(stderr, "error: lparen delimiter followed by space\n");
+                        return (Tokens){0};
+                    }
+                }
+
+                if (token_n != 0) {
+                    fprintf(stderr, "error: lparen delimiter within symbol name\n");
+                    return (Tokens){0};
+                }
+                // Push paren token.
+                tokens_buf[n++] = (StringView){
+                    .start = &sv.start[i],
+                    .n = 1,
+                };
+            } break;
+            case ')': {
+                if ((i + 1 < sv.n)) {
+                    char next_c = sv.start[i + 1];
+                    if ((next_c != ')' && !isspace(next_c))) {
+                        fprintf(stderr, "error: rparen delimiter within symbol name\n");
+                        return (Tokens){0};
+                    }
+                }
+
+                if (token_n != 0) {
+                    // Push previous token.
+                    tokens_buf[n++] = (StringView){
+                        .start = &sv.start[i - token_n],
+                        .n = token_n,
+                    };
+                    token_n = 0;
+                }
+
+                // Push paren token.
+                tokens_buf[n++] = (StringView){
+                    .start = &sv.start[i],
+                    .n = 1,
+                };
+            } break;
+            default: {
+                token_n++;
+            } break;
+        }
+    }
+    if (token_n != 0) {
+        // End of line encountered.
+        tokens_buf[n++] = (StringView){
+            .start = &sv.start[sv.n - token_n],
+            .n = token_n,
+        };
+    }
+
+    // DEBUG: Printing tokens.
+    printf("N_TOKENS: %ld\n", n);
+    for (size_t i = 0; i < n; i++) {
+        printf("TOKEN: ");
+        sv_write(tokens_buf[i]);
+        printf("\tN: %ld", tokens_buf[i].n);
+        printf("\n");
+    }
+
+    return (Tokens){.start = (StringView *)&tokens_buf, .n = n};
+}
+
 void
 display(StringView sv) {
     if (sv.n != 0) {
@@ -55,7 +161,9 @@ main(void) {
     printf("BDL REPL (Press Ctrl-C to exit)\n");
     while (true) {
         printf(REPL_PROMPT);
-        display(read_line());
+        StringView line = read_line();
+        tokenize(line);
+        display(line);
     }
     return 0;
 }
-- 
cgit v1.2.1