+/*
+ File name : fprintf.c
+ Date of creation : 05/12/2022
+ Version : 1.0
+ Copyright : Soft'n'design
+ Author : Laurent Mazet <mazet@softndesign.org>
+
+ Description : This file contains embedded printf
+
+ History :
+ - initial version
+*/
+
+#include <stdarg.h>
+#include <stdint.h>
+#include <unistd.h>
+
+#include "fdprintf.h"
+
+int _fd_stdout = STDOUT_FILENO;
+int _fd_stderr = STDERR_FILENO;
+
+unsigned int nextpow (unsigned int x, int base) {
+ unsigned int n = 0;
+ while (x) {
+ n++;
+ x = x / base;
+ }
+ return (n == 0) ? 1 : n;
+}
+
+/* simple fprintf function */
+
+int fdprintf (int fd, const char *fmt, ...)
+{
+ char buffer[1024 + 1] = { 0 };
+ char *str = buffer;
+
+ va_list ap;
+ va_start (ap, fmt);
+ while (*fmt) {
+ char *s;
+ int d = 0;
+ unsigned int u;
+ char c = *fmt++;
+
+ /* copy standard char */
+ if (c != '%') {
+ *str++ = c;
+ } else {
+ int t = 0;
+ char w = '0';
+ int i, sz = 0;
+ void *p = NULL;
+
+ /* stamp */
+ if ((*fmt == ' ') || (*fmt == '0')) {
+ w = *fmt++;
+ }
+
+ /* size */
+ if ((*fmt >= '1') && (*fmt <= '9')) {
+ sz = *fmt++ - '0';
+ }
+
+ /* process format char */
+ switch (*fmt++) {
+ case 'c': /* char */
+ c = (char) va_arg (ap, int);
+ *str++ = c;
+ break;
+ case 'd': /* int */
+ d = va_arg (ap, int);
+ if (d < 0) {
+ *str++ = '-';
+ d = -d;
+ }
+ t = 1;
+ /* fall through */
+ case 'u': /* unsigned int */
+ u = (t) ? (unsigned int)d : va_arg (ap, unsigned int);
+ for (i = nextpow (u, 10), s = str; i > 0; i--, s++) {
+ str[i - 1] = '0' + (u % 10);
+ u /= 10;
+ }
+ str = s;
+ break;
+ case 'p': /* pointer */
+ *str++ = '0';
+ *str++ = 'x';
+ w = '0';
+ sz = sizeof (void *) * 2;
+ p = va_arg (ap, void *);
+ /* fall through */
+ case 'x': /* integer hexa */
+ if (!p) {
+ u = va_arg (ap, unsigned int);
+ if (sz == 0) {
+ sz = nextpow (u, 16);
+ }
+ } else {
+ u = (uintptr_t)p;
+ }
+ for (i = sz, t = 1; i > 0; i--) {
+ char x = (char)((u >> (i * 4 - 4)) & 0xf);
+ if ((t == 1) && (x == 0)) {
+ *str++ = w;
+ } else {
+ *str++ = (x > 9) ? 'a' + x - 10 : '0' + x;
+ t = 0;
+ }
+ }
+ break;
+ case 's': /* string */
+ s = va_arg (ap, char *);
+ while (s && *s)
+ *str++ = *s++;
+ break;
+ default:
+ *str++ = '?';
+ }
+ }
+ }
+ va_end (ap);
+
+ /* output string */
+ int n = str - buffer;
+ if (n < (int)sizeof (buffer) - 1) {
+ return write (fd, buffer, n);
+ }
+ return 0;
+}
+
+/* vim: set ts=4 sw=4 et: */