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-rw-r--r--lib/libc/stdio/vfprintf.c809
1 files changed, 809 insertions, 0 deletions
diff --git a/lib/libc/stdio/vfprintf.c b/lib/libc/stdio/vfprintf.c
new file mode 100644
index 00000000..fb4c200e
--- /dev/null
+++ b/lib/libc/stdio/vfprintf.c
@@ -0,0 +1,809 @@
+#include <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stddef.h>
+#include <math.h>
+#include <unistd.h>
+#include <wchar.h>
+
+extern char *dtoa(double, int mode, int ndigits, int *decpt, int *sign,
+ char **rve);
+extern void freedtoa(char *s);
+
+static int utoa_base(unsigned long long v, char *s, int b, int p, int u)
+{
+ const char *d = u ? "0123456789ABCDEF" : "0123456789abcdef";
+ char buf[65];
+ int i = 0, j;
+ if (p < 0)
+ p = 0;
+ if (p > 64)
+ p = 64;
+ do {
+ buf[i++] = d[v % b];
+ v /= b;
+ } while (v && i < 64);
+ while (i < p && i < 64)
+ buf[i++] = '0';
+ for (j = 0; j < i; ++j)
+ s[j] = buf[i - j - 1];
+ s[i] = 0;
+ return i;
+}
+
+int vfprintf(FILE *restrict stream, const char *restrict format, va_list ap)
+{
+ const char *ptr;
+ int total_printed;
+
+ ptr = format;
+ total_printed = 0;
+
+ while (*ptr != '\0') {
+ if (*ptr != '%') {
+ fputc(*ptr, stream);
+ total_printed++;
+ ptr++;
+ } else {
+ char *s = NULL;
+ char buf[128];
+ int l = 0;
+ int width = 0;
+ int padding = 0;
+ int precision = -1;
+
+ ptr++;
+
+ enum {
+ FLAG_NONE = 0,
+ FLAG_MINUS = 1 << 0,
+ FLAG_PLUS = 1 << 1,
+ FLAG_HASH = 1 << 2,
+ FLAG_ZERO = 1 << 3,
+ FLAG_SPACE = 1 << 4
+ } flags = FLAG_NONE;
+
+ enum {
+ LENGTH_NONE,
+ LENGTH_HH,
+ LENGTH_H,
+ LENGTH_L,
+ LENGTH_LL,
+ LENGTH_J,
+ LENGTH_Z,
+ LENGTH_T,
+ LENGTH_CAPL
+ } length = LENGTH_NONE;
+
+ while (*ptr == '-' || *ptr == '+' || *ptr == ' ' ||
+ *ptr == '0' || *ptr == '#') {
+ if (*ptr == '-')
+ flags |= FLAG_MINUS;
+ else if (*ptr == '+')
+ flags |= FLAG_PLUS;
+ else if (*ptr == ' ')
+ flags |= FLAG_SPACE;
+ else if (*ptr == '0')
+ flags |= FLAG_ZERO;
+ else if (*ptr == '#')
+ flags |= FLAG_HASH;
+ ptr++;
+ }
+
+ if (*ptr == '*') {
+ width = va_arg(ap, int);
+ if (width < 0) {
+ flags |= FLAG_MINUS;
+ width = -width;
+ }
+ ptr++;
+ } else {
+ while (isdigit(*ptr)) {
+ width = width * 10 + (*ptr - '0');
+ ptr++;
+ }
+ }
+
+ if (*ptr == '.') {
+ ptr++;
+ if (*ptr == '*') {
+ precision = va_arg(ap, int);
+ if (precision < 0)
+ precision = -1;
+ ptr++;
+ } else {
+ precision = 0;
+ while (isdigit(*ptr)) {
+ precision = precision * 10 +
+ (*ptr - '0');
+ ptr++;
+ }
+ }
+ }
+
+ switch (*ptr) {
+ case 'h':
+ if (*(ptr + 1) == 'h') {
+ length = LENGTH_HH;
+ ptr++;
+ } else
+ length = LENGTH_H;
+ ptr++;
+ break;
+ case 'l':
+ if (*(ptr + 1) == 'l') {
+ length = LENGTH_LL;
+ ptr++;
+ } else
+ length = LENGTH_L;
+ ptr++;
+ break;
+ case 'L':
+ length = LENGTH_CAPL;
+ ptr++;
+ break;
+ case 'j':
+ length = LENGTH_J;
+ ptr++;
+ break;
+ case 'z':
+ length = LENGTH_Z;
+ ptr++;
+ break;
+ case 't':
+ length = LENGTH_T;
+ ptr++;
+ break;
+ }
+
+ switch (*ptr) {
+ case 'i':
+ case 'd': {
+ long long val;
+ int negative = 0;
+
+ switch (length) {
+ case LENGTH_NONE:
+ val = va_arg(ap, int);
+ break;
+ case LENGTH_HH:
+ val = (signed char)va_arg(ap, int);
+ break;
+ case LENGTH_H:
+ val = (short)va_arg(ap, int);
+ break;
+ case LENGTH_L:
+ val = va_arg(ap, long);
+ break;
+ case LENGTH_LL:
+ val = va_arg(ap, long long);
+ break;
+ case LENGTH_J:
+ val = va_arg(ap, intmax_t);
+ break;
+ case LENGTH_Z:
+ val = va_arg(ap, ssize_t);
+ break;
+ case LENGTH_T:
+ val = va_arg(ap, ptrdiff_t);
+ break;
+ case LENGTH_CAPL:
+ errno = EINVAL;
+ return -1;
+ }
+
+ unsigned long long uval;
+
+ if (val < 0) {
+ uval = (unsigned long long)(-val);
+ negative = 1;
+ } else {
+ uval = (unsigned long long)val;
+ }
+
+ l = utoa_base(uval, buf, 10, precision, 0);
+
+ s = buf;
+ if (negative) {
+ memmove(s + 1, s, l);
+ s[0] = '-';
+ s[++l] = '\0';
+ } else if (flags & FLAG_PLUS) {
+ memmove(s + 1, s, l);
+ s[0] = '+';
+ s[++l] = '\0';
+ } else if (flags & FLAG_SPACE) {
+ memmove(s + 1, s, l);
+ s[0] = ' ';
+ s[++l] = '\0';
+ }
+
+ break;
+ }
+ case 'o':
+ case 'u':
+ case 'x':
+ case 'X': {
+ unsigned long long val;
+ char fmt_char = *ptr;
+
+ switch (length) {
+ case LENGTH_NONE:
+ val = va_arg(ap, unsigned int);
+ break;
+ case LENGTH_HH:
+ val = (unsigned char)va_arg(
+ ap, unsigned int);
+ break;
+ case LENGTH_H:
+ val = (unsigned short)va_arg(
+ ap, unsigned int);
+ break;
+ case LENGTH_L:
+ val = va_arg(ap, unsigned long);
+ break;
+ case LENGTH_LL:
+ val = va_arg(ap, unsigned long long);
+ break;
+ case LENGTH_J:
+ val = va_arg(ap, uintmax_t);
+ break;
+ case LENGTH_Z:
+ val = va_arg(ap, size_t);
+ break;
+ case LENGTH_T:
+ val = (ptrdiff_t)va_arg(ap, ptrdiff_t);
+ break;
+ case LENGTH_CAPL:
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (fmt_char == 'o') {
+ l = utoa_base(val, buf, 8, precision,
+ 0);
+ } else if (fmt_char == 'u') {
+ l = utoa_base(val, buf, 10, precision,
+ 0);
+ } else if (fmt_char == 'x') {
+ l = utoa_base(val, buf, 16, precision,
+ 0);
+ } else if (fmt_char == 'X') {
+ l = utoa_base(val, buf, 16, precision,
+ 1);
+ } else {
+ l = utoa_base(val, buf, 10, precision,
+ 0);
+ }
+
+ s = buf;
+
+ if ((flags & FLAG_HASH) && val != 0) {
+ if (fmt_char == 'o') {
+ memmove(s + 1, s, l);
+ s[0] = '0';
+ s[++l] = '\0';
+ } else if (fmt_char == 'x') {
+ memmove(s + 2, s, l);
+ s[0] = '0';
+ s[1] = 'x';
+ l += 2;
+ s[l] = '\0';
+ } else if (fmt_char == 'X') {
+ memmove(s + 2, s, l);
+ s[0] = '0';
+ s[1] = 'X';
+ l += 2;
+ s[l] = '\0';
+ }
+ }
+
+ break;
+ }
+
+ case 'f':
+ case 'F':
+ case 'e':
+ case 'E':
+ case 'g':
+ case 'G': {
+ double val;
+
+ if (length == LENGTH_CAPL)
+ val = (double)va_arg(ap, long double);
+ else
+ val = va_arg(ap, double);
+
+ if (precision == -1)
+ precision = 6;
+
+ s = buf;
+ int pos = 0;
+
+ if (isnan(val)) {
+ strcpy(buf,
+ (*ptr == 'F' || *ptr == 'E' ||
+ *ptr == 'G') ?
+ "NAN" :
+ "nan");
+ l = 3;
+ break;
+ }
+ if (isinf(val)) {
+ if (val < 0) {
+ buf[pos++] = '-';
+ } else if (flags & FLAG_PLUS) {
+ buf[pos++] = '+';
+ } else if (flags & FLAG_SPACE) {
+ buf[pos++] = ' ';
+ }
+ strcpy(buf + pos,
+ (*ptr == 'F' || *ptr == 'E' ||
+ *ptr == 'G') ?
+ "INF" :
+ "inf");
+ l = pos + 3;
+ break;
+ }
+
+ if (val < 0) {
+ buf[pos++] = '-';
+ val = -val;
+ } else if (flags & FLAG_PLUS) {
+ buf[pos++] = '+';
+ } else if (flags & FLAG_SPACE) {
+ buf[pos++] = ' ';
+ }
+
+ switch (*ptr) {
+ case 'f':
+ case 'F': {
+ int decpt, sign;
+ char *rve;
+ char *digits = dtoa(val, 3, precision,
+ &decpt, &sign,
+ &rve);
+
+ if (sign && val != 0.0) {
+ buf[pos++] = '-';
+ }
+
+ if (decpt <= 1 && digits[0] == '0' &&
+ digits[1] == '\0') {
+ buf[pos++] = '0';
+ if (precision > 0) {
+ buf[pos++] = '.';
+ for (int i = 0;
+ i < precision;
+ i++) {
+ buf[pos++] =
+ '0';
+ }
+ }
+ } else if (decpt <= 0) {
+ buf[pos++] = '0';
+ if (precision > 0) {
+ buf[pos++] = '.';
+ for (int i = 0;
+ i < -decpt &&
+ i < precision;
+ i++) {
+ buf[pos++] =
+ '0';
+ }
+ int remaining =
+ precision +
+ decpt;
+ char *d = digits;
+ while (*d &&
+ remaining-- >
+ 0) {
+ buf[pos++] =
+ *d++;
+ }
+ while (remaining-- >
+ 0) {
+ buf[pos++] =
+ '0';
+ }
+ }
+ } else {
+ char *d = digits;
+ int digits_used = 0;
+ for (int i = 0; i < decpt && *d;
+ i++) {
+ buf[pos++] = *d++;
+ digits_used++;
+ }
+ while (digits_used < decpt) {
+ buf[pos++] = '0';
+ digits_used++;
+ }
+ if (precision > 0) {
+ buf[pos++] = '.';
+ for (int i = 0;
+ i < precision;
+ i++) {
+ if (*d) {
+ buf[pos++] =
+ *d++;
+ } else {
+ buf[pos++] =
+ '0';
+ }
+ }
+ }
+ }
+
+ buf[pos] = '\0';
+ l = pos;
+ freedtoa(digits);
+ break;
+ }
+ case 'e':
+ case 'E': {
+ int decpt, sign;
+ char *rve;
+ char *digits =
+ dtoa(val, 2, precision + 1,
+ &decpt, &sign, &rve);
+
+ if (sign && val != 0.0) {
+ buf[pos++] = '-';
+ }
+
+ if (*digits) {
+ buf[pos++] = *digits++;
+ } else {
+ buf[pos++] = '0';
+ }
+
+ if (precision > 0) {
+ buf[pos++] = '.';
+ for (int i = 0; i < precision;
+ i++) {
+ if (*digits) {
+ buf[pos++] =
+ *digits++;
+ } else {
+ buf[pos++] =
+ '0';
+ }
+ }
+ }
+
+ buf[pos++] = (*ptr == 'E') ? 'E' : 'e';
+ int exp = decpt - 1;
+ buf[pos++] = (exp >= 0) ? '+' : '-';
+ if (exp < 0)
+ exp = -exp;
+ if (exp < 10)
+ buf[pos++] = '0';
+ pos += utoa_base(exp, buf + pos, 10, 0,
+ 0);
+
+ buf[pos] = '\0';
+ l = pos;
+ freedtoa(digits);
+ break;
+ }
+ case 'g':
+ case 'G': {
+ int decpt, sign;
+ char *rve;
+ char *digits = dtoa(val, 2, precision,
+ &decpt, &sign,
+ &rve);
+
+ if (sign && val != 0.0) {
+ buf[pos++] = '-';
+ }
+
+ int exp = decpt - 1;
+ if (exp < -4 || exp >= precision) {
+ if (*digits) {
+ buf[pos++] = *digits++;
+ }
+ if (*digits) {
+ buf[pos++] = '.';
+ while (*digits) {
+ buf[pos++] =
+ *digits++;
+ }
+ }
+ buf[pos++] = (*ptr == 'G') ?
+ 'E' :
+ 'e';
+ buf[pos++] = (exp >= 0) ? '+' :
+ '-';
+ if (exp < 0)
+ exp = -exp;
+ if (exp < 10)
+ buf[pos++] = '0';
+ pos += utoa_base(exp, buf + pos,
+ 10, 0, 0);
+ } else {
+ if (decpt <= 0) {
+ buf[pos++] = '0';
+ if (*digits &&
+ *digits != '0') {
+ buf[pos++] =
+ '.';
+ for (int i = 0;
+ i < -decpt;
+ i++) {
+ buf[pos++] =
+ '0';
+ }
+ char *d =
+ digits;
+ while (*d &&
+ *d != '0') {
+ buf[pos++] =
+ *d++;
+ }
+ }
+ } else {
+ char *d = digits;
+ for (int i = 0;
+ i < decpt && *d;
+ i++) {
+ buf[pos++] =
+ *d++;
+ }
+ if (*d) {
+ buf[pos++] =
+ '.';
+ while (*d) {
+ buf[pos++] =
+ *d++;
+ }
+ }
+ }
+ }
+
+ while (pos > 1 && buf[pos - 1] == '0' &&
+ pos > 2 && buf[pos - 2] != 'e' &&
+ buf[pos - 2] != 'E') {
+ pos--;
+ }
+ if (pos > 1 && buf[pos - 1] == '.') {
+ pos--;
+ }
+
+ buf[pos] = '\0';
+ l = pos;
+ freedtoa(digits);
+ break;
+ }
+ }
+
+ break;
+ }
+
+ case 'a':
+ case 'A': {
+ double val;
+
+ if (length == LENGTH_CAPL)
+ val = (double)va_arg(ap, long double);
+ else
+ val = va_arg(ap, double);
+
+ int upper = (*ptr == 'A');
+ int pos = 0;
+
+ if (val < 0) {
+ buf[pos++] = '-';
+ val = -val;
+ } else if (flags & FLAG_PLUS) {
+ buf[pos++] = '+';
+ } else if (flags & FLAG_SPACE) {
+ buf[pos++] = ' ';
+ }
+
+ if (val == 0.0) {
+ strcpy(buf + pos,
+ upper ? "0X0P+0" : "0x0p+0");
+ l = pos + 6;
+ break;
+ }
+
+ int exp;
+ double mant = frexp(val, &exp);
+ mant *= 2.0;
+ exp--;
+
+ buf[pos++] = '0';
+ buf[pos++] = upper ? 'X' : 'x';
+ buf[pos++] = '1';
+
+ if (precision == -1) {
+ precision = 13;
+ }
+
+ if (precision > 0) {
+ buf[pos++] = '.';
+ mant -= 1.0;
+ for (int i = 0; i < precision; i++) {
+ mant *= 16.0;
+ int digit = (int)mant;
+ if (digit > 15)
+ digit = 15;
+ buf[pos++] =
+ (digit < 10) ?
+ ('0' + digit) :
+ (upper ? ('A' +
+ digit -
+ 10) :
+ ('a' +
+ digit -
+ 10));
+ mant -= digit;
+ }
+
+ while (pos > 0 && buf[pos - 1] == '0') {
+ pos--;
+ }
+ if (pos > 0 && buf[pos - 1] == '.') {
+ pos--;
+ }
+ }
+
+ buf[pos++] = upper ? 'P' : 'p';
+ if (exp >= 0) {
+ buf[pos++] = '+';
+ } else {
+ buf[pos++] = '-';
+ exp = -exp;
+ }
+ pos += utoa_base(exp, buf + pos, 10, 0, 0);
+
+ buf[pos] = '\0';
+ s = buf;
+ l = pos;
+ break;
+ }
+
+ case 'C':
+ length = LENGTH_L;
+ /* fallthrough */
+ case 'c': {
+ if (length == LENGTH_L) {
+ } else {
+ char c = (char)va_arg(ap, int);
+ buf[0] = c;
+ buf[1] = '\0';
+ s = buf;
+ l = 1;
+ }
+ break;
+ }
+
+ case 'S':
+ length = LENGTH_L;
+ /* fallthrough */
+ case 's':
+ if (length == LENGTH_L) {
+ } else {
+ s = va_arg(ap, char *);
+ l = strlen(s);
+ if (precision >= 0 && precision < l)
+ l = precision;
+ }
+ break;
+
+ case 'p': {
+ void *ptr_val = va_arg(ap, void *);
+ uintptr_t uptr = (uintptr_t)ptr_val;
+ int len = utoa_base((unsigned long long)uptr,
+ buf + 2, 16,
+ sizeof(void *) * 2, 0);
+ buf[0] = '0';
+ buf[1] = 'x';
+ buf[len + 2] = '\0';
+ l = len + 2;
+ s = buf;
+ break;
+ }
+
+ case 'n': {
+ int *ip = va_arg(ap, int *);
+ if (ip != NULL) {
+ *ip = total_printed;
+ }
+ l = 0;
+ break;
+ }
+ case '%': {
+ buf[0] = '%';
+ s = buf;
+ l = 1;
+ break;
+ }
+ default:
+ errno = EINVAL;
+ return -1;
+ }
+
+ ptr++;
+
+ if (l < width) {
+ padding = width - l;
+ }
+
+ char format_char = *(ptr - 1);
+ char pad_char = ' ';
+ if ((flags & FLAG_ZERO) && !(flags & FLAG_MINUS) &&
+ (format_char == 'd' || format_char == 'i' ||
+ format_char == 'u' || format_char == 'o' ||
+ format_char == 'x' || format_char == 'X' ||
+ format_char == 'f' || format_char == 'F' ||
+ format_char == 'e' || format_char == 'E' ||
+ format_char == 'g' || format_char == 'G') &&
+ precision < 0) {
+ pad_char = '0';
+ }
+
+ if ((flags & FLAG_MINUS) == 0) {
+ if (pad_char == '0' && s != NULL) {
+ int prefix_len = 0;
+
+ if (s[0] == '-' || s[0] == '+' ||
+ s[0] == ' ') {
+ fwrite(s, 1, 1, stream);
+ total_printed++;
+ s++;
+ l--;
+ prefix_len++;
+ }
+
+ if (l >= 2 && s[0] == '0' &&
+ (s[1] == 'x' || s[1] == 'X')) {
+ fwrite(s, 1, 2, stream);
+ total_printed += 2;
+ s += 2;
+ l -= 2;
+ prefix_len += 2;
+ }
+
+ for (int i = 0; i < padding; i++) {
+ fwrite("0", 1, 1, stream);
+ total_printed++;
+ }
+ } else {
+ for (int i = 0; i < padding; i++) {
+ if (pad_char == '0') {
+ fwrite("0", 1, 1,
+ stream);
+ } else {
+ fwrite(" ", 1, 1,
+ stream);
+ }
+ total_printed++;
+ }
+ }
+ }
+
+ if (l > 0) {
+ if (s != NULL)
+ fwrite(s, 1, l, stream);
+ total_printed += l;
+ }
+
+ if (flags & FLAG_MINUS) {
+ for (int i = 0; i < padding; i++) {
+ fwrite(" ", 1, 1, stream);
+ total_printed++;
+ }
+ }
+ }
+ }
+
+ return total_printed;
+}
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