diff options
| author | EmulatedSeasons <89668582+EmulatedSeasons@users.noreply.github.com> | 2024-07-18 22:25:44 -0400 |
|---|---|---|
| committer | EmulatedSeasons <89668582+EmulatedSeasons@users.noreply.github.com> | 2024-09-03 14:07:04 -0400 |
| commit | 8eda325ede02d3fc606a34f7fa3c4922b05a84e4 (patch) | |
| tree | 881da3ba217871a002e6e79bdfc90149cc589e1d /libc/printf.c | |
| parent | 82bcab74e6e0c581dcf4ac4d7997aec5c5e14aae (diff) | |
Remerged the std stuff into the kernel
Diffstat (limited to 'libc/printf.c')
| -rw-r--r-- | libc/printf.c | 199 |
1 files changed, 0 insertions, 199 deletions
diff --git a/libc/printf.c b/libc/printf.c deleted file mode 100644 index 0bb5506..0000000 --- a/libc/printf.c +++ /dev/null @@ -1,199 +0,0 @@ -#include <limits.h>
-#include <stdbool.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <string.h>
-#include <stdint.h>
-
-static bool print(const char* data, size_t length) {
- const unsigned char* bytes = (const unsigned char*) data;
- for (size_t i = 0; i < length; i++)
- if (putchar(bytes[i]) == EOF)
- return false;
- return true;
-}
-
-// for %d and %x.
-static const char* itoa(unsigned int num, char* str, unsigned int base) {
- int cou = 0; // nt
-
- if (num == 0) { // 0
- str[cou] = '0';
- str[++cou] = '\0';
- return str;
- }
-
- while (num)
- {
- unsigned int rem = (num % base);
- // brings the number up to ascii 0 + the digit
- if (rem > 9) {
- str[cou] = rem + '7'; // 7 = 55 + 10(A) = 65
- } else {
- str[cou] = rem + '0';
- }
- num /= base;
- ++cou;
- }
-
- // reverse the string
- size_t start = 0;
- size_t end = cou - 1;
- while (start < end) {
- char temp = str[start];
- str[start] = str[end];
- str[end] = temp;
- ++start;
- --end;
- }
-
- str[cou] = '\0';
- return str;
-}
-
-// have no idea if there's a better way to do this. for %lx
-static const char* itoa_u64(unsigned long long num, char* str, int base) {
- size_t cou = 0; // nt
-
- if (num == 0) { // 0
- str[cou] = '0';
- str[++cou] = '\0';
- return str;
- }
-
- while (num)
- {
- unsigned long long rem = num % base;
- // brings the number up to ascii 0 + the digit
- if (rem > 9) {
- str[cou] = rem + '7'; // 7 = 55 + 10(A) = 65
- } else {
- str[cou] = rem + '0';
- }
- num /= base;
- ++cou;
- }
-
- // reverse the string
- size_t start = 0;
- size_t end = cou - 1;
- while (start < end) {
- char temp = str[start];
- str[start] = str[end];
- str[end] = temp;
- ++start;
- --end;
- }
-
- str[cou] = '\0';
- return str;
-}
-
-int printf(const char* restrict format, ...) {
- va_list parameters;
- va_start(parameters, format);
-
- int written = 0;
-
- while (*format != '\0') {
- size_t maxrem = INT_MAX - written;
-
- if (format[0] != '%' || format[1] == '%') {
- if (format[0] == '%')
- format++;
- size_t amount = 1;
- while (format[amount] && format[amount] != '%')
- amount++;
- if (maxrem < amount) {
- // TODO: Set errno to EOVERFLOW.
- return -1;
- }
- if (!print(format, amount))
- return -1;
- format += amount;
- written += amount;
- continue;
- }
-
- const char* format_begun_at = format++;
-
- if (*format == 'c') {
- format++;
- char c = (char) va_arg(parameters, int /* char promotes to int */);
- if (!maxrem) {
- // TODO: Set errno to EOVERFLOW.
- return -1;
- }
- if (!print(&c, sizeof(c)))
- return -1;
- written++;
- } else if (*format == 'd') {
- format++;
- char str[20]; // probably a long enough buffer
- unsigned int d = va_arg(parameters, unsigned int);
- itoa(d, str, 10);
- size_t len = strlen(str);
- if (maxrem < len) {
- // TODO: Set errno to EOVERFLOW.
- return -1;
- }
- if (!print(str, len))
- return -1;
- written += len;
- } else if (*format == 'x') {
- format++;
- char str[20]; // probably a long enough buffer
- unsigned int d = va_arg(parameters, unsigned int);
- itoa(d, str, 16);
- size_t len = strlen(str);
- if (maxrem < len) {
- // TODO: Set errno to EOVERFLOW.
- return -1;
- }
- if (!print(str, len))
- return -1;
- written += len;
- } else if (*format == 'l') { // for %lx and others that start with l
- format++;
- if (*format == 'x') {
- format++;
- char str[20]; // probably a long enough buffer
- unsigned long long d = va_arg(parameters, unsigned long long);
- itoa_u64(d, str, 16);
- size_t len = strlen(str);
- if (maxrem < len) {
- // TODO: Set errno to EOVERFLOW.
- return -1;
- }
- if (!print(str, len))
- return -1;
- written += len;
- }
- } else if (*format == 's') {
- format++;
- const char* str = va_arg(parameters, const char*);
- size_t len = strlen(str);
- if (maxrem < len) {
- // TODO: Set errno to EOVERFLOW.
- return -1;
- }
- if (!print(str, len))
- return -1;
- written += len;
- } else {
- format = format_begun_at;
- size_t len = strlen(format);
- if (maxrem < len) {
- // TODO: Set errno to EOVERFLOW.
- return -1;
- }
- if (!print(format, len))
- return -1;
- written += len;
- format += len;
- }
- }
-
- va_end(parameters);
- return written;
-}
\ No newline at end of file |