From c85f4e85a1906d94b0b4b2e212c11b7b42f6afc0 Mon Sep 17 00:00:00 2001
From: Renge <renge@renge.io>
Date: Sat, 12 Feb 2022 16:47:38 -0500
Subject: [PATCH] feat: implemented validargs.c

---
 hw1/src/validargs.c | 105 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 101 insertions(+), 4 deletions(-)

diff --git a/hw1/src/validargs.c b/hw1/src/validargs.c
index c218d35..6cf49d6 100644
--- a/hw1/src/validargs.c
+++ b/hw1/src/validargs.c
@@ -20,7 +20,104 @@
  * of the selected program options.
  */
 
-int validargs(int argc, char **argv) {
-    // TO BE IMPLEMENTED
-    abort();
-}
+int validargs(int argc, char **argv)
+{
+    char **ptr = argv;
+    ptr++;
+    for (int i = 1; i < argc; i++, ptr++)
+    {
+        if (**ptr == '-')
+        {
+            char *arg = *ptr;
+            arg++;
+            switch (*arg)
+            {
+            case 'h':
+                if (i == 1 && *(++arg) == '\0')
+                {
+                    global_options = HELP_OPTION;
+                    return 0;
+                }
+                else
+                {
+                    return -1;
+                }
+                break;
+            case 'v':
+                if (i == 1 && *(++arg) == '\0' && argc == 2)
+                {
+                    global_options = VALIDATE_OPTION;
+                    return 0;
+                }
+                else
+                {
+                    return -1;
+                }
+                break;
+            case 'c':
+                if (i == 1 && *(++arg) == '\0')
+                {
+                    if (argc == 2)
+                    {
+                        global_options = CANONICALIZE_OPTION;
+                        return 0;
+                    }
+                    else
+                    {
+                        ptr++;
+                        if (**ptr != '-')
+                        {
+                            return -1;
+                        }
+                        arg = *ptr;
+                        if (*(++arg) != 'p')
+                        {
+                            return -1;
+                        }
+                        if (*(++arg) != '\0')
+                        {
+                            return -1;
+                        }
+                        global_options = PRETTY_PRINT_OPTION;
+                        if (argc == 3)
+                        {
+                            return 0;
+                        }
+                        else if (argc == 4)
+                        {
+                            int indent_value = 0;
+                            arg = *(++ptr);
+                            while (*arg != '\0')
+                            {
+                                if (*arg <= '9' && *arg >= '0')
+                                {
+                                    indent_value = indent_value * 10 + (*arg - '0');
+                                    arg++;
+                                }
+                                else
+                                {
+                                    return 1;
+                                }
+                            }
+                            global_options += indent_value;
+                            return 0;
+                        }
+                        else
+                        {
+                            return -1;
+                        }
+                    }
+                }
+                else
+                {
+                    return -1;
+                }
+                break;
+            default:
+                return -1;
+                break;
+            }
+        }
+    }
+    return -1;
+}
\ No newline at end of file