From adab797391e46cec1018e37866a6f136f10c56a3 Mon Sep 17 00:00:00 2001
From: Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com>
Date: Mon, 21 Oct 2013 11:51:02 +0900
Subject: [PATCH] add system.c

---
 include/picrin.h |  5 +++-
 src/init.c       |  2 ++
 src/state.c      |  7 ++++-
 src/system.c     | 72 ++++++++++++++++++++++++++++++++++++++++++++++++
 tools/main.c     |  4 +--
 5 files changed, 86 insertions(+), 4 deletions(-)
 create mode 100644 src/system.c

diff --git a/include/picrin.h b/include/picrin.h
index b7cd063e..ec593460 100644
--- a/include/picrin.h
+++ b/include/picrin.h
@@ -17,6 +17,9 @@ typedef struct pic_callinfo {
 } pic_callinfo;
 
 typedef struct {
+  int argc;
+  char **argv, **envp;
+
   pic_value *sp;
   pic_value *stbase, *stend;
 
@@ -56,7 +59,7 @@ void pic_gc_protect(pic_state *, pic_value);
 int pic_gc_arena_preserve(pic_state *);
 void pic_gc_arena_restore(pic_state *, int);
 
-pic_state *pic_open();
+pic_state *pic_open(int argc, char *argv[], char **envp);
 void pic_close(pic_state *);
 
 void pic_get_args(pic_state *, const char *, ...);
diff --git a/src/init.c b/src/init.c
index 2c330247..a4d0407d 100644
--- a/src/init.c
+++ b/src/init.c
@@ -3,6 +3,7 @@
 void pic_init_port(pic_state *);
 void pic_init_number(pic_state *);
 void pic_init_time(pic_state *);
+void pic_init_system(pic_state *);
 
 #define DONE pic_gc_arena_restore(pic, ai);
 
@@ -15,4 +16,5 @@ pic_init_core(pic_state *pic)
   pic_init_port(pic); DONE;
   pic_init_number(pic); DONE;
   pic_init_time(pic); DONE;
+  pic_init_system(pic); DONE;
 }
diff --git a/src/state.c b/src/state.c
index 09bc261f..5cebdac9 100644
--- a/src/state.c
+++ b/src/state.c
@@ -35,13 +35,18 @@ sym_tbl_new()
 void pic_init_core(pic_state *);
 
 pic_state *
-pic_open()
+pic_open(int argc, char *argv[], char **envp)
 {
   pic_state *pic;
   int ai;
 
   pic = (pic_state *)malloc(sizeof(pic_state));
 
+  /* command line */
+  pic->argc = argc;
+  pic->argv = argv;
+  pic->envp = envp;
+
   /* prepare VM stack */
   pic->stbase = pic->sp = (pic_value *)malloc(sizeof(pic_value) * PIC_STACK_SIZE);
   pic->stend = pic->stbase + PIC_STACK_SIZE;
diff --git a/src/system.c b/src/system.c
new file mode 100644
index 00000000..04c38804
--- /dev/null
+++ b/src/system.c
@@ -0,0 +1,72 @@
+#include <stdlib.h>
+
+#include "picrin.h"
+#include "picrin/pair.h"
+
+static pic_value
+pic_system_cmdline(pic_state *pic)
+{
+  pic_value v = pic_nil_value();
+  int i;
+
+  pic_get_args(pic, "");
+
+  for (i = 0; i < pic->argc; ++i) {
+    int ai = pic_gc_arena_preserve(pic);
+
+    v = pic_cons(pic, pic_str_new_cstr(pic, pic->argv[i]), v);
+    pic_gc_arena_restore(pic, ai);
+  }
+
+  return v;
+}
+
+static pic_value
+pic_system_getenv(pic_state *pic)
+{
+  char *str, *val;
+  size_t len;
+
+  pic_get_args(pic, "s", &str, &len);
+
+  val = getenv(str);
+
+  return pic_str_new_cstr(pic, val);
+}
+
+static pic_value
+pic_system_getenvs(pic_state *pic)
+{
+  char **envp;
+  pic_value data = pic_nil_value();
+  int ai = pic_gc_arena_preserve(pic);
+
+  pic_get_args(pic, "");
+
+  for (envp = pic->envp; *envp; ++envp) {
+    pic_value key, val;
+    int i;
+
+    for (i = 0; (*envp)[i] != '='; ++i)
+      ;
+
+    key = pic_str_new(pic, *envp, i);
+    val = pic_str_new_cstr(pic, getenv(*envp));
+
+    /* push */
+    data = pic_acons(pic, key, val, data);
+
+    pic_gc_arena_restore(pic, ai);
+    pic_gc_protect(pic, data);
+  }
+
+  return data;
+}
+
+void
+pic_init_system(pic_state *pic)
+{
+  pic_defun(pic, "command-line", pic_system_cmdline);
+  pic_defun(pic, "get-environment-variable", pic_system_getenv);
+  pic_defun(pic, "get-environment-variables", pic_system_getenvs);
+}
diff --git a/tools/main.c b/tools/main.c
index a8f752cc..275e01dd 100644
--- a/tools/main.c
+++ b/tools/main.c
@@ -13,7 +13,7 @@
 #define LINE_MAX_LENGTH 256
 
 int
-main()
+main(int argc, char *argv[], char **envp)
 {
   pic_state *pic;
   char code[CODE_MAX_LENGTH] = "", line[LINE_MAX_LENGTH];
@@ -28,7 +28,7 @@ main()
   int char_index;
 #endif
 
-  pic = pic_open();
+  pic = pic_open(argc, argv, envp);
 
   ai = pic_gc_arena_preserve(pic);