From 4e09bca9e34c226b6d7e34b4fa11248405fd988e Mon Sep 17 00:00:00 2001 From: Anton Kling Date: Sun, 22 Oct 2023 19:50:38 +0200 Subject: Move everything into a new repo. --- userland/libc/stdio/vfprintf.c | 243 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 243 insertions(+) create mode 100644 userland/libc/stdio/vfprintf.c (limited to 'userland/libc/stdio/vfprintf.c') diff --git a/userland/libc/stdio/vfprintf.c b/userland/libc/stdio/vfprintf.c new file mode 100644 index 0000000..79a22fb --- /dev/null +++ b/userland/libc/stdio/vfprintf.c @@ -0,0 +1,243 @@ +#include +#include +#include +#include + +const char HEX_SET[0x10] = {'0', '1', '2', '3', '4', '5', '6', '7', + '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'}; + +#define FILE_WRITE(_f, _s, _l, _r) \ + { \ + size_t _rc = _f->write(_f, (const unsigned char *)_s, _l); \ + if ((size_t)-1 == _rc) \ + assert(0); \ + *(int *)(_r) += _rc; \ + } +// if ((size_t)0 == _rc) \ +// assert(0); \ + +int fprint_num(FILE *f, int n, int base, char *char_set, int prefix, + int zero_padding, int right_padding) { + int c = 0; + if (0 == n) { + zero_padding = 1; + prefix = 1; + } + char str[32]; + int i = 0; + for (; n != 0 && i < 32; i++, n /= base) + // str[i] = (n % base) + '0'; + str[i] = char_set[(n % base)]; + + char t = (zero_padding) ? '0' : ' '; + int orig_i = i; + + if (!right_padding) { + for (; prefix - orig_i > 0; prefix--) + FILE_WRITE(f, &t, 1, &c); + } + + for (i--; i >= 0; i--) + FILE_WRITE(f, &(str[i]), 1, &c); + + if (right_padding) { + for (; prefix - orig_i > 0; prefix--) + FILE_WRITE(f, &t, 1, &c); + } + return c; +} + +int fprint_int(FILE *f, int n, int prefix, int zero_padding, + int right_padding) { + return fprint_num(f, n, 10, "0123456789", prefix, zero_padding, + right_padding); +} + +int fprint_hex(FILE *f, int n, int prefix, int zero_padding, + int right_padding) { + return fprint_num(f, n, 16, "0123456789abcdef", prefix, zero_padding, + right_padding); +} + +int fprint_octal(FILE *f, int n, int prefix, int zero_padding, + int right_padding) { + return fprint_num(f, n, 8, "012345678", prefix, zero_padding, right_padding); +} + +int print_string(FILE *f, const char *s, int *rc, int prefix, int right_padding, + int precision) { + int l = strlen(s); + char t = ' '; + int c = 0; + if (!right_padding) { + if (prefix) + assert(-1 == precision); // FIXME: Is this correct? + for (; prefix - l > 0; prefix--) + FILE_WRITE(f, &t, 1, &c); + } + int bl = precision; + for (; *s; s++, (*rc)++) { + if (precision != -1) { + if (0 == bl) + break; + bl--; + } + int r; + FILE_WRITE(f, (const unsigned char *)s, 1, &r); + assert(r != 0); + } + if (right_padding) { + assert(-1 == precision); // FIXME: Is this correct? + for (; prefix - l > 0; prefix--) + FILE_WRITE(f, &t, 1, &c); + } + (*rc) += c; + return 0; +} + +int parse_precision(const char **fmt) { + const char *s = *fmt; + int rc = 0; + for (int i = 0;; i++, s++) { + if ('\0' == *s) + break; + const char c = *s; + if ('*' == c) { + assert(i == 0); + return -1; + } else if (!(c >= '0' && c <= '9')) { + s--; + break; + } + rc *= 10; + rc += c - '0'; + } + *fmt = s; + return rc; +} + +int vfprintf(FILE *f, const char *fmt, va_list ap) { + int rc = 0; + const char *s = fmt; + int prefix = 0; + + int zero_padding = 0; + int right_padding = 0; + + int cont = 0; + int precision = -1; + for (; *s; s++) { + if (!cont && '%' != *s) { + FILE_WRITE(f, (const unsigned char *)s, 1, &rc); + continue; + } + if (!cont) { + cont = 1; + continue; + } + + if ('\0' == *s) + break; + + switch (*s) { + case '.': + s++; + assert('\0' != *s); + precision = parse_precision(&s); + assert('\0' != *s); + if (-1 == precision) + precision = va_arg(ap, int); + cont = 1; + break; + case '0': + prefix *= 10; + if (0 == prefix) + zero_padding = 1; + cont = 1; + break; + case '-': + assert(0 == prefix); + right_padding = 1; + cont = 1; + break; + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + prefix *= 10; + prefix += (*s) - '0'; + cont = 1; + break; + case 'i': + case 'd': + if(-1 != precision) { + zero_padding = 1; + prefix = precision; + right_padding = 0; + } + rc += fprint_int(f, va_arg(ap, int), prefix, zero_padding, right_padding); + cont = 0; + break; + case 'u': + assert(-1 == precision); + rc += fprint_int(f, va_arg(ap, unsigned int), prefix, zero_padding, + right_padding); + cont = 0; + break; + case 's': { + assert(!zero_padding); // this is not supported to strings + char *a = va_arg(ap, char *); + if (!a) { + if (-1 == + print_string(f, "(NULL)", &rc, prefix, right_padding, precision)) + return -1; + cont = 0; + break; + } + if (-1 == print_string(f, a, &rc, prefix, right_padding, precision)) + return -1; + cont = 0; + break; + } + case 'p': // TODO: Print this out in a nicer way + case 'x': + assert(-1 == precision); + rc += fprint_hex(f, va_arg(ap, const uint32_t), prefix, zero_padding, + right_padding); + cont = 0; + break; + case 'o': + assert(-1 == precision); + rc += fprint_octal(f, va_arg(ap, const uint32_t), prefix, zero_padding, + right_padding); + cont = 0; + break; + case '%': { + FILE_WRITE(f, (const unsigned char *)"%", 1, &rc); + cont = 0; + break; + } + case 'c': { + char c = va_arg(ap, const int); + FILE_WRITE(f, (const unsigned char *)&c, 1, &rc); + cont = 0; + break; + } + default: + printf("got %c but that is not supported by printf\n", *s); + assert(0); + break; + } + if (!cont) { + prefix = 0; + zero_padding = right_padding = 0; + precision = -1; + } + } + return rc; +} -- cgit v1.2.3