From fd02ee26e1038b0f4761430e164d53bb1b5908dc Mon Sep 17 00:00:00 2001
From: josh <josh@5b3e749e-e535-0410-8002-a9bb6afbdfca>
Date: Wed, 15 Jul 2009 14:53:58 +0000
Subject: [PATCH] added kputs_pad(); implemented padding in kprintf(); put some
 padding tests in k_main()

git-svn-id: svn://anubis/hos/trunk@57 5b3e749e-e535-0410-8002-a9bb6afbdfca
---
 kernel/boot/k_main.cc |  4 +++
 kernel/lang/kio.cc    | 58 +++++++++++++++++++++++++++++++++----------
 kernel/lang/kio.h     |  2 ++
 3 files changed, 51 insertions(+), 13 deletions(-)

diff --git a/kernel/boot/k_main.cc b/kernel/boot/k_main.cc
index 2dd9f10..7c1ac64 100644
--- a/kernel/boot/k_main.cc
+++ b/kernel/boot/k_main.cc
@@ -6,6 +6,10 @@ extern "C" {
 void k_main()
 {
     kprintf("Hi from k_main()!\n");
+    kprintf("padded 8 hex: 0x%08x|\n", 0x42);
+    kprintf("padded -4 hex: 0x%-4x|\n", 0x42);
+    kprintf("padded  20 str: %20s|\n", "hi there");
+    kprintf("padded -20 str: %-20s|\n", "hi there");
 }
 
 } /* extern "C" */
diff --git a/kernel/lang/kio.cc b/kernel/lang/kio.cc
index f4edce3..257904a 100644
--- a/kernel/lang/kio.cc
+++ b/kernel/lang/kio.cc
@@ -57,16 +57,29 @@ void kvprintf(const char * fmt, va_list args)
             if (*fmt)
             {
                 int width = 0;
-                char pad = ' ';
+                char pad_char = ' ';
+                bool pad_right = false;
                 if (*fmt == '0')
                 {
-                    pad = '0';
+                    pad_char = '0';
                     fmt++;
                 }
-                if ('1' <= *fmt && *fmt <= '9')
+                else if (*fmt == '-')
                 {
-                    width = *fmt - '0';
-                    /* TODO: finish */
+                    pad_right = true;
+                    fmt++;
+                }
+                for ( ; '0' <= *fmt && *fmt <= '9'; fmt++)
+                {
+                    if (width == 0)
+                    {
+                        width = *fmt - '0';
+                    }
+                    else
+                    {
+                        width *= 10;
+                        width += *fmt - '0';
+                    }
                 }
                 switch (*fmt)
                 {
@@ -75,34 +88,35 @@ void kvprintf(const char * fmt, va_list args)
                         break;
                     case 'd':
                         fmt_d2a(tmpbuf, va_arg(args, int));
-                        kputs(tmpbuf);
+                        kputs_pad(tmpbuf, width, pad_char, pad_right);
                         break;
                     case 'l':
                         fmt_ll2a(tmpbuf, va_arg(args, long long));
-                        kputs(tmpbuf);
+                        kputs_pad(tmpbuf, width, pad_char, pad_right);
                         break;
                     case 'L':
                         fmt_ull2a(tmpbuf, va_arg(args, unsigned long long));
-                        kputs(tmpbuf);
+                        kputs_pad(tmpbuf, width, pad_char, pad_right);
                         break;
                     case 'o':
                         fmt_o2a(tmpbuf, va_arg(args, unsigned int));
-                        kputs(tmpbuf);
+                        kputs_pad(tmpbuf, width, pad_char, pad_right);
                         break;
                     case 's':
-                        kputs(va_arg(args, char *));
+                        kputs_pad(va_arg(args, char *),
+                                  width, pad_char, pad_right);
                         break;
                     case 'u':
                         fmt_u2a(tmpbuf, va_arg(args, unsigned int));
-                        kputs(tmpbuf);
+                        kputs_pad(tmpbuf, width, pad_char, pad_right);
                         break;
                     case 'x':
                         fmt_x2a(tmpbuf, va_arg(args, unsigned int));
-                        kputs(tmpbuf);
+                        kputs_pad(tmpbuf, width, pad_char, pad_right);
                         break;
                     case 'X':
                         fmt_xl2a(tmpbuf, va_arg(args, unsigned long long));
-                        kputs(tmpbuf);
+                        kputs_pad(tmpbuf, width, pad_char, pad_right);
                         break;
                     case '%':
                         kputc('%');
@@ -170,6 +184,24 @@ void kputs(const char * s)
     }
 }
 
+void kputs_pad(const char * s, int width, char pad_char, bool pad_right)
+{
+    int len = strlen(s);
+    if (pad_right)
+    {
+        kputs(s);
+    }
+    int num_pad_chars = width - len;
+    for (int i = 0; i < num_pad_chars; i++)
+    {
+        kputc(pad_char);
+    }
+    if (!pad_right)
+    {
+        kputs(s);
+    }
+}
+
 } /* extern "C" */
 
 static void fmt_d2a(char * buf, int val)
diff --git a/kernel/lang/kio.h b/kernel/lang/kio.h
index 925b407..5e577a6 100644
--- a/kernel/lang/kio.h
+++ b/kernel/lang/kio.h
@@ -18,6 +18,8 @@ void kputc(char c);
 
 void kputs(const char * s);
 
+void kputs_pad(const char * s, int width, char pad_char, bool pad_right);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif