# HG changeset patch
# User John Tsiombikas <nuclear@member.fsf.org>
# Date 1292764027 -7200
# Node ID 633e35c64772740186895372bbf6d1509a9e9698
# Parent  0489a34ab348d9c41f4651f2a5940027ec68a2cf
- added printf family in stdio.c
- added atoi/atol in stdlib.c
- added nonstandard itoa/utoa in stdlib.c
- added strlen/strchr/strrchr in string.c

diff -r 0489a34ab348 -r 633e35c64772 src/klibc/stdio.c
--- a/src/klibc/stdio.c	Fri Dec 10 03:44:34 2010 +0200
+++ b/src/klibc/stdio.c	Sun Dec 19 15:07:07 2010 +0200
@@ -1,4 +1,9 @@
 #include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+
+static void bwrite(char *buf, size_t buf_sz, char *str, int sz);
+static int intern_printf(char *buf, size_t sz, const char *fmt, va_list ap);
 
 /* putchar is defined in term.c */
 
@@ -10,3 +15,243 @@
 	putchar('\n');
 	return 0;
 }
+
+/* -- printf and friends -- */
+
+static char *convc = "dioxXucsfeEgGpn%";
+
+#define IS_CONV(c)	strchr(convc, c)
+
+int printf(const char *fmt, ...)
+{
+	int res;
+	va_list ap;
+
+	va_start(ap, fmt);
+	res = intern_printf(0, 0, fmt, ap);
+	va_end(ap);
+	return res;
+}
+
+int vprintf(const char *fmt, va_list ap)
+{
+	return intern_printf(0, 0, fmt, ap);
+}
+
+int sprintf(char *buf, const char *fmt, ...)
+{
+	int res;
+	va_list ap;
+
+	va_start(ap, fmt);
+	res = intern_printf(buf, 0, fmt, ap);
+	va_end(ap);
+	return res;
+}
+
+int vsprintf(char *buf, const char *fmt, va_list ap)
+{
+	return intern_printf(buf, 0, fmt, ap);
+}
+
+int snprintf(char *buf, size_t sz, const char *fmt, ...)
+{
+	int res;
+	va_list ap;
+
+	va_start(ap, fmt);
+	res = intern_printf(buf, sz, fmt, ap);
+	va_end(ap);
+	return res;
+}
+
+int vsnprintf(char *buf, size_t sz, const char *fmt, va_list ap)
+{
+	return intern_printf(buf, sz, fmt, ap);
+}
+
+
+/* intern_printf provides all the functionality needed by all the printf
+ * variants.
+ * - buf: optional buffer onto which the formatted results are written. If null
+ *   then the output goes to the terminal through putchar calls. This is used
+ *   by the (v)sprintf variants which write to an array of char.
+ * - sz: optional maximum size of the output, 0 means unlimited. This is used
+ *   by the (v)snprintf variants to avoid buffer overflows.
+ * The rest are obvious, format string and variable argument list.
+ */
+
+#define BUF(x)	((x) ? (x) + cnum : (x))
+#define SZ(x)	((x) ? (x) - cnum : (x))
+
+static int intern_printf(char *buf, size_t sz, const char *fmt, va_list ap)
+{
+	char conv_buf[32];
+	char *str;
+	int i, slen;
+	const char *fstart = 0;
+
+	/* state */
+	int cnum = 0;
+	int base = 10;
+	int alt = 0;
+	int fwidth = 0;
+	int padc = ' ';
+	int sign = 0;
+	int left_align = 0;	/* not implemented yet */
+	int hex_caps = 0;
+	int unsig = 0;
+
+	while(*fmt) {
+		if(*fmt == '%') {
+			fstart = fmt++;
+			continue;
+		}
+
+		if(fstart) {
+			if(IS_CONV(*fmt)) {
+				switch(*fmt) {
+				case 'X':
+					hex_caps = 1;
+
+				case 'x':
+				case 'p':
+					base = 16;
+
+					if(alt) {
+						bwrite(BUF(buf), SZ(sz), "0x", 2);
+					}
+
+				case 'u':
+					unsig = 1;
+
+					if(0) {
+				case 'o':
+						base = 8;
+
+						if(alt) {
+							bwrite(BUF(buf), SZ(sz), "0", 1);
+						}
+					}
+
+				case 'd':
+				case 'i':
+					if(unsig) {
+						utoa(va_arg(ap, unsigned int), conv_buf, base);
+					} else {
+						itoa(va_arg(ap, int), conv_buf, base);
+					}
+					if(hex_caps) {
+						for(i=0; conv_buf[i]; i++) {
+							conv_buf[i] = toupper(conv_buf[i]);
+						}
+					}
+
+					slen = strlen(conv_buf);
+					for(i=slen; i<fwidth; i++) {
+						bwrite(BUF(buf), SZ(sz), (char*)&padc, 1);
+						cnum++;
+					}
+
+					bwrite(BUF(buf), SZ(sz), conv_buf, strlen(conv_buf));
+					cnum += slen;
+					break;
+
+				case 'c':
+					{
+						char c = va_arg(ap, int);
+						bwrite(BUF(buf), SZ(sz), &c, 1);
+						cnum++;
+					}
+					break;
+
+				case 's':
+					str = va_arg(ap, char*);
+					slen = strlen(str);
+
+					for(i=slen; i<fwidth; i++) {
+						bwrite(BUF(buf), SZ(sz), (char*)&padc, 1);
+						cnum++;
+					}
+					bwrite(BUF(buf), SZ(sz), str, slen);
+					cnum += slen;
+					break;
+
+				case 'n':
+					*va_arg(ap, int*) = cnum;
+					break;
+
+				default:
+					break;
+				}
+
+				/* restore default conversion state */
+				base = 10;
+				alt = 0;
+				fwidth = 0;
+				padc = ' ';
+				hex_caps = 0;
+
+				fstart = 0;
+				fmt++;
+			} else {
+				switch(*fmt) {
+				case '#':
+					alt = 1;
+					break;
+
+				case '+':
+					sign = 1;
+					break;
+
+				case '-':
+					left_align = 1;
+					break;
+
+				case 'l':
+				case 'L':
+					break;
+
+				case '0':
+					padc = '0';
+					break;
+
+				default:
+					if(isdigit(*fmt)) {
+						const char *fw = fmt;
+						while(*fmt && isdigit(*fmt)) fmt++;
+
+						fwidth = atoi(fw);
+						continue;
+					}
+				}
+				fmt++;
+			}
+		} else {
+			bwrite(BUF(buf), SZ(sz), (char*)fmt++, 1);
+			cnum++;
+		}
+	}
+
+	return 0;
+}
+
+
+/* bwrite is called by intern_printf to transparently handle writing into a
+ * buffer (if buf is non-null) or to the terminal (if buf is null).
+ */
+static void bwrite(char *buf, size_t buf_sz, char *str, int sz)
+{
+	if(buf) {
+		if(buf_sz && buf_sz <= sz) sz = buf_sz - 1;
+		memcpy(buf, str, sz);
+
+		buf[sz] = 0;
+	} else {
+		int i;
+		for(i=0; i<sz; i++) {
+			putchar(*str++);
+		}
+	}
+}
+
diff -r 0489a34ab348 -r 633e35c64772 src/klibc/stdio.h
--- a/src/klibc/stdio.h	Fri Dec 10 03:44:34 2010 +0200
+++ b/src/klibc/stdio.h	Sun Dec 19 15:07:07 2010 +0200
@@ -1,7 +1,19 @@
 #ifndef STDIO_H_
 #define STDIO_H_
 
+#include <stdlib.h>
+#include <stdarg.h>
+
 int putchar(int c);
 int puts(const char *s);
 
+int printf(const char *fmt, ...);
+int vprintf(const char *fmt, va_list ap);
+
+int sprintf(char *buf, const char *fmt, ...);
+int vsprintf(char *buf, const char *fmt, va_list ap);
+
+int snprintf(char *buf, size_t sz, const char *fmt, ...);
+int vsnprintf(char *buf, size_t sz, const char *fmt, va_list ap);
+
 #endif	/* STDIO_H_ */
diff -r 0489a34ab348 -r 633e35c64772 src/klibc/stdlib.h
--- a/src/klibc/stdlib.h	Fri Dec 10 03:44:34 2010 +0200
+++ b/src/klibc/stdlib.h	Sun Dec 19 15:07:07 2010 +0200
@@ -6,4 +6,10 @@
 typedef int32_t ssize_t;
 typedef uint32_t size_t;
 
+int atoi(const char *str);
+long atol(const char *str);
+
+void itoa(int val, char *buf, int base);
+void utoa(unsigned int val, char *buf, int base);
+
 #endif	/* STDLIB_H_ */
diff -r 0489a34ab348 -r 633e35c64772 src/klibc/string.c
--- a/src/klibc/string.c	Fri Dec 10 03:44:34 2010 +0200
+++ b/src/klibc/string.c	Sun Dec 19 15:07:07 2010 +0200
@@ -54,3 +54,37 @@
 
 	return dest;
 }
+
+size_t strlen(const char *s)
+{
+	size_t len = 0;
+	while(*s++) len++;
+	return len;
+}
+
+char *strchr(const char *s, int c)
+{
+	while(*s) {
+		if(*s == c) {
+			return s;
+		}
+		s++;
+	}
+	return 0;
+}
+
+char *strrchr(const char *s, int c)
+{
+	char *ptr = s;
+
+	/* find the end */
+	while(*ptr) ptr++;
+
+	/* go back checking for c */
+	while(*--ptr >= s) {
+		if(*ptr == c) {
+			return ptr;
+		}
+	}
+	return 0;
+}
diff -r 0489a34ab348 -r 633e35c64772 src/klibc/string.h
--- a/src/klibc/string.h	Fri Dec 10 03:44:34 2010 +0200
+++ b/src/klibc/string.h	Sun Dec 19 15:07:07 2010 +0200
@@ -9,4 +9,9 @@
 void *memcpy(void *dest, const void *src, size_t n);
 void *memmove(void *dest, const void *src, size_t n);
 
+size_t strlen(const char *s);
+
+char *strchr(const char *s, int c);
+char *strrchr(const char *s, int c);
+
 #endif	/* STRING_H_ */