mirb - Embeddable Interactive Ruby Shell

3 files changed, 312 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index 5229393b6..4f85c6c00 100644
--- a/Makefile
+++ b/Makefile
@@ -26,8 +26,16 @@ all :
 	@$(MAKE) -C mrblib $(MAKE_FLAGS)
 	@$(MAKE) -C tools/mruby $(MAKE_FLAGS)
 
+.PHONY : mirb
+mirb :
+	@$(MAKE) -C src $(MAKE_FLAGS)
+	@$(MAKE) -C mrblib $(MAKE_FLAGS)
+	@$(MAKE) -C tools/mirb $(MAKE_FLAGS)
+
 # clean up
 .PHONY : clean
 clean :
 	@$(MAKE) clean -C src $(MAKE_FLAGS)
 	@$(MAKE) clean -C tools/mruby $(MAKE_FLAGS)
+	@$(MAKE) clean -C tools/mirb $(MAKE_FLAGS)
+
diff --git a/tools/mirb/Makefile b/tools/mirb/Makefile
new file mode 100644
index 000000000..37086879d
--- /dev/null
+++ b/tools/mirb/Makefile
@@ -0,0 +1,74 @@
+# makefile discription.
+# basic build file for mirb executable
+
+# project-specific macros
+# extension of the executable-file is modifiable(.exe .out ...)
+BASEDIR = ../../src
+TARGET := ../../bin/mirb
+LIBR := ../../lib/libmruby.a
+ifeq ($(OS),Windows_NT)
+  EXE := $(TARGET).exe
+else
+  EXE := $(TARGET)
+endif
+OBJ0 := $(patsubst %.c,%.o,$(wildcard $(BASEDIR)/../tools/mirb/*.c))
+OBJS := $(OBJ0)
+
+# ext libraries
+EXTS := $(EXT1)
+
+# libraries, includes
+LIBS = -lm
+INCLUDES = -I$(BASEDIR) -I$(BASEDIR)/../include
+
+# compiler, linker (gcc)
+CC = gcc
+LL = gcc
+YACC = bison
+DEBUG_MODE = 1
+ifeq ($(DEBUG_MODE),1)
+  CFLAGS = -g -O3
+else
+  CFLAGS = -O3
+endif
+ALL_CFLAGS = -Wall -Werror-implicit-function-declaration $(CFLAGS)
+ifeq ($(OS),Windows_NT)
+  MAKE_FLAGS = CC=$(CC) LL=$(LL) ALL_CFLAGS="$(ALL_CFLAGS)"
+else
+  MAKE_FLAGS = CC='$(CC)' LL='$(LL)' ALL_CFLAGS='$(ALL_CFLAGS)'
+endif
+
+##############################
+# generic build targets, rules
+
+.PHONY : all
+all : $(LIBR) $(EXE)
+	@echo "make: built targets of `pwd`"
+
+# executable constructed using linker from object files
+$(EXE) : $(LIBR) $(OBJS) $(EXTS)
+	$(LL) -o $@ $(CFLAGS) $(OBJS) $(LIBR) $(EXTS) $(LIBS)
+
+-include $(OBJS:.o=.d)
+
+# objects compiled from source
+$(OBJS) : %.o : %.c
+	$(CC) $(ALL_CFLAGS) -MMD $(INCLUDES) -c $< -o $@
+
+# C library compile
+$(LIBR) :
+	@$(MAKE) -C $(BASEDIR) $(MAKE_FLAGS)
+
+# mruby library compile
+# extend libraries complile
+$(EXTS) : %.o : %.c
+	$(CC) $(ALL_CFLAGS) -MMD $(INCLUDES) -c $< -o $@
+
+# clean up
+.PHONY : clean #cleandep
+clean :
+	$(MAKE) clean -C ../../mrblib $(MAKE_FLAGS)
+	$(MAKE) clean -C ../mrbc $(MAKE_FLAGS)
+	@echo "make: removing targets, objects and depend files of `pwd`"
+	-rm -f $(EXE) $(OBJS)
+	-rm -f $(OBJS:.o=.d)
diff --git a/tools/mirb/mirb.c b/tools/mirb/mirb.c
new file mode 100644
index 000000000..3089d288f
--- /dev/null
+++ b/tools/mirb/mirb.c
@@ -0,0 +1,230 @@
+/*
+** mirb - Embeddable Interactive Ruby Shell
+**
+** This program takes code from the user in
+** an interactive way and executes it
+** immediately. It's a REPL...
+*/
+ 
+#include <string.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include <mruby.h>
+#include <mruby/proc.h>
+#include <mruby/data.h>
+#include <compile.h>
+
+/* Guess if the user might want to enter more
+ * or if he wants an evaluation of his code now */
+bool is_code_block_open(struct mrb_parser_state *parser) {
+  bool code_block_open = false;
+
+  switch (parser->lstate) {
+
+  // all states which need more code
+
+  case EXPR_BEG:
+    // an expression was just started,
+    // we can't end it like this
+    code_block_open = true;
+    break;
+  case EXPR_DOT:
+    // a message dot was the last token,
+    // there has to come more
+    code_block_open = true;
+    break;
+  case EXPR_CLASS:
+    // a class keyword is not enough!
+    // we need also a name of the class
+    code_block_open = true;
+    break;
+  case EXPR_FNAME:
+    // a method name is necessary
+    code_block_open = true;
+    break;
+  case EXPR_VALUE:
+    // if, elsif, etc. without condition
+    code_block_open = true;
+    break;
+
+  // now all the states which are closed
+
+  case EXPR_ARG:
+    // an argument is the last token
+    code_block_open = false;
+    break;
+  case EXPR_CMDARG:
+    code_block_open = false;
+    break;
+
+  // all states which are unsure
+
+  case EXPR_END:
+    // an expression was ended
+    break;
+  case EXPR_ENDARG:
+    // closing parenthese
+    break;
+  case EXPR_ENDFN:
+    // definition end
+    break;
+  case EXPR_MID:
+    // jump keyword like break, return, ...
+    break;
+  case EXPR_MAX_STATE:
+    // don't know what to do with this token
+    break;
+  default:
+    // this state is unexpected!
+    break;
+  }
+
+  if (!code_block_open) {
+    // based on the last parser state the code
+    // block seems to be open
+
+    // now check if parser error are available
+    if (0 < parser->nerr) {
+      // a parser error occur, we have to check if
+      // we need to read one more line or if there is
+      // a different issue which we have to show to
+      // the user
+
+      if (strcmp(parser->error_buffer[0].message,
+          "syntax error, unexpected $end, expecting ';' or '\\n'") == 0) {
+        code_block_open = true;
+      } else if (strcmp(parser->error_buffer[0].message,
+          "syntax error, unexpected $end, expecting keyword_end") == 0) {
+        code_block_open = true;
+      } else if (strcmp(parser->error_buffer[0].message,
+          "syntax error, unexpected $end, expecting '<' or ';' or '\\n'") == 0) {
+        code_block_open = true;
+      } else if (strcmp(parser->error_buffer[0].message,
+          "syntax error, unexpected keyword_end") == 0) {
+        code_block_open = true;
+      } else if (strcmp(parser->error_buffer[0].message,
+          "syntax error, unexpected $end, expecting keyword_then or ';' or '\\n'") == 0) {
+        code_block_open = true;
+      } else if (strcmp(parser->error_buffer[0].message,
+          "syntax error, unexpected tREGEXP_BEG") == 0) {
+        code_block_open = true;
+      }
+    }
+  } else {
+    // last parser state suggest that this code
+    // block is open, WE NEED MORE CODE!!
+  }
+
+  return code_block_open;
+}
+
+/* Print a short remark for the user */
+void print_hint(void)
+{
+  printf("mirb - Embeddable Interactive Ruby Shell\n");
+  printf("\nThis is a very early version, please test and report errors.\n");
+  printf("Thanks :)\n\n");
+}
+
+/* Print the command line prompt of the REPL */
+void print_cmdline(bool code_block_open) {
+  if (code_block_open) {
+    printf("* ");
+  } else {
+    printf("> ");
+  }
+}
+
+int main(void)
+{
+  char last_char, ruby_code[1024], last_code_line[1024];
+  int char_index;
+  struct mrb_parser_state *parser;
+  mrb_state *mrb_interpreter;
+  mrb_value mrb_return_value;
+  int byte_code;
+  bool code_block_open = false;
+
+  print_hint();
+
+  // new interpreter instance
+  mrb_interpreter = mrb_open();
+  memset(ruby_code, 0, sizeof(*ruby_code));
+  memset(last_code_line, 0, sizeof(*last_code_line));
+
+  while (true) {
+    print_cmdline(code_block_open);
+
+    char_index = 0;
+    while ((last_char = getchar()) != '\n') {
+      if (last_char == EOF) break;
+      last_code_line[char_index++] = last_char;
+    }
+    if (last_char == EOF) {
+      printf("\n");
+      break;
+    }
+
+    last_code_line[char_index] = '\0';
+
+    if (strcmp(last_code_line, "exit") == 0) {
+      if (code_block_open) {
+        // cancel the current block and reset
+        code_block_open = false;
+        memset(ruby_code, 0, sizeof(*ruby_code));
+        memset(last_code_line, 0, sizeof(*last_code_line));
+        continue;
+      } else {
+        // quit the program
+        break;
+      }
+    } else {
+      if (code_block_open) {
+        strcat(ruby_code, "\n");
+        strcat(ruby_code, last_code_line);
+      } else {
+        memset(ruby_code, 0, sizeof(*ruby_code));
+        strcat(ruby_code, last_code_line);
+      }
+
+      // parse code
+      parser = mrb_parse_nstring_ext(mrb_interpreter, ruby_code, strlen(ruby_code));
+      code_block_open = is_code_block_open(parser); 
+
+      if (code_block_open) {
+        // no evaluation of code
+      } else {
+        if (0 < parser->nerr) {
+          // syntax error
+          printf("%s\n", parser->error_buffer[0].message);
+        } else {
+          // generate bytecode
+          byte_code = mrb_generate_code(mrb_interpreter, parser->tree);
+
+          // evaluate the bytecode
+          mrb_return_value = mrb_run(mrb_interpreter,
+            // pass a proc for evaulation
+            mrb_proc_new(mrb_interpreter, mrb_interpreter->irep[byte_code]),
+            mrb_top_self(mrb_interpreter));
+            //mrb_nil_value());
+          // did an exception occur?
+          if (mrb_interpreter->exc) {
+            mrb_p(mrb_interpreter, mrb_obj_value(mrb_interpreter->exc));
+            mrb_interpreter->exc = 0;
+          } else {
+            // no
+            printf(" => ");
+            mrb_p(mrb_interpreter, mrb_return_value);
+          }
+        }
+
+        memset(ruby_code, 0, sizeof(*ruby_code));
+        memset(ruby_code, 0, sizeof(*last_code_line));
+      }
+    }
+  }
+
+  return 0;
+}