jitters: add option parsing

src/jitters.c

@@ -1,21 +1,105 @@
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
+
+#include <argp.h>
+
+#include "config.h"
 
 #include "ast/ast.h"
-#include "print/printer.h"
+#include "compile/compiler.h"
+#include "eval/evaluator.h"
 #include "parse/parse-jitters.h"
+#include "print/printer.h"
 
-int main(void)
+const char *argp_program_version = PACKAGE_STRING;
+const char *argp_program_bug_address = "<" PACKAGE_BUGREPORT ">";
+
+static char doc[] =
+    PACKAGE_NAME " -- an experiment in interpreters and compilers";
+
+
+static struct argp_option options[] = {
+    {"evaluate", 'e', 0,      0,  "Evaluate input by walking the tree" },
+    {"compile",  'c', 0,      0,  "Compile input to assembly" },
+    {"print",    'p', 0,      0,  "Print parsed expression" },
+    {"output",   'o', "FILE", 0,  "Output to FILE instead of standard output" },
+    {"debug",    'd', 0,      0,  "Emit debug output from parser" },
+    { 0 }
+};
+
+struct arguments
+{
+    bool debug; // Whether to activate Bison using debug trace
+    bool compile; // Whether to compile the input
+    bool evaluate; // Whether to evaluate the input
+    bool print; // Whether to print the input
+    const char *output_file; // Where to output
+};
+
+static error_t parse_opt(int key, char *arg, struct argp_state *state)
+{
+    struct arguments *arguments = state->input;
+
+    switch (key)
+    {
+    case 'c':
+        arguments->compile = true;
+        break;
+    case 'd':
+        arguments->debug = true;
+        break;
+    case 'e':
+        arguments->evaluate = true;
+        break;
+    case 'p':
+        arguments->print = true;
+        break;
+    case 'o':
+        arguments->output_file = arg;
+        break;
+    case ARGP_KEY_ARG:
+        argp_usage(state);
+        break;
+    case ARGP_KEY_END:
+        break;
+    default:
+        return ARGP_ERR_UNKNOWN;
+    }
+    return 0;
+}
+
+static struct argp argp = { options, parse_opt, 0, doc };
+
+int main(int argc, char *argv[])
 {
     struct ast_node *ast = NULL;
     int ret = 0;
-    yydebug = getenv("PARSE") != NULL;
+    struct arguments arguments = {
+        .output_file = "-",
+    };
+    FILE *output = stdout;
+
+    argp_parse(&argp, argc, argv, 0, 0, &arguments);
+
+    yydebug = getenv("PARSE") != NULL || arguments.debug;
+
+    if (strcmp(arguments.output_file, "-"))
+        output = fopen(arguments.output_file, "w");
+
     if ((ret = yyparse(&ast)) == 0) {
-        printer_ast(ast);
-        putchar('\n');
+        if (arguments.compile)
+            compile_ast(ast, output);
+        if (arguments.evaluate)
+            fprintf(output, "%d\n", evaluate_ast(ast));
+        if (arguments.print)
+            print_ast(ast, output);
     }
 
     destroy_ast(ast);
+    if (strcmp(arguments.output_file, "-"))
+        fclose(output);
 
     return ret;
 }