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-rw-r--r--lib/kprintf.c653
1 files changed, 0 insertions, 653 deletions
diff --git a/lib/kprintf.c b/lib/kprintf.c
deleted file mode 100644
index 3d803f6..0000000
--- a/lib/kprintf.c
+++ /dev/null
@@ -1,653 +0,0 @@
-#include <lib/kstdio.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdbool.h>
-
-enum specifier_type
-{
- INVALID_PRINT,
- CHARACTER_PRINT,
- STRING_PRINT,
- INTEGER_PRINT,
- COUNT_PRINT
-};
-
-enum specifier_flags
-{
- INVALID_FLAGS,
- LEFT_JUSTIFY_FLAG = 0x1,
- EXPLICIT_SIGN_FLAG = 0x2,
- PAD_SIGN_FLAG = 0x4,
- SIGNED_TYPE_FLAG = 0x8,
- SIGN_FLAG_MASK = 0x6,
- ALTERNATE_FORM_FLAG = 0x10,
- ZERO_PAD_FLAG = 0x20,
-};
-
-enum specifier_integer_base
-{
- INVALID_BASE,
- BIN_BASE = 2,
- OCT_BASE = 8,
- DEC_BASE = 10,
- HEX_BASE = 16
-};
-
-enum specifier_integer_width
-{
- INVALID_WIDTH,
- BYTE_WIDTH = 8,
- SHORT_WIDTH = 16,
- INT_WIDTH = 32,
- LONG_WIDTH = 64
-};
-
-struct method
-{
- int (*write_character)(struct method *m, char c);
- int (*write_wcharacter)(struct method *m, wchar_t c);
- int (*write_string)(struct method *m, const char *s);
- int (*write_wstring)(struct method *m, const wchar_t *s);
- void *output;
- int count;
-};
-
-struct specifier
-{
- enum specifier_type type;
- enum specifier_flags flags;
- enum specifier_integer_width integer_width;
- enum specifier_integer_base integer_base;
- int field_width;
- int field_precision;
- size_t length;
-};
-
-static struct specifier parse_specifier(const char *format, va_list *arguments)
-{
- struct specifier result =
- {
- INVALID_PRINT,
- INVALID_FLAGS,
- INVALID_WIDTH,
- INVALID_BASE,
- 0,
- 0,
- 0
- };
-
- // keep a pointer to the beginning of the specifier
- const char *begin = format;
-
- // step 1: scan for flags
- bool flags_parsed = false;
-
- while (!flags_parsed)
- {
- switch (*begin)
- {
- case 0:
- result.type = INVALID_PRINT;
- return result;
- case '-':
- result.flags |= LEFT_JUSTIFY_FLAG;
- begin++;
- break;
- case '+':
- result.flags |= EXPLICIT_SIGN_FLAG;
- begin++;
- break;
- case ' ':
- result.flags |= PAD_SIGN_FLAG;
- begin++;
- break;
- case '#':
- result.flags |= ALTERNATE_FORM_FLAG;
- begin++;
- break;
- case '0':
- result.flags |= ZERO_PAD_FLAG;
- begin++;
- break;
- default:
- flags_parsed = true;
- }
- }
-
- // step 2: parse field width and precision
- // TODO: parse field width and precision
- /* procedure:
- * 1. check if next character is * or .
- * a. if *, field width is the value pointed to by the next item in
- * arguments list
- * b. if ., field width will be set to 0, proceed to 3.
- * 2. if above check is false, check for numeric character
- * a. if is numeric character, parse field width via strtoul, add length
- * of numeric string to begin.
- * b. if is not a numeric character, skip check for width and precision
- * entirely
- * 3. check if next character is * or numeric
- * a. if *, field precision is the value pointed to by the next item
- * in arguments list.
- * b. if is numeric character, parse field precision via strtoul, add
- * length of numeric string to begin.
- */
- bool field_width_parsed = false;
- bool field_precision_parsed = false;
-
- while (!field_width_parsed || !field_precision_parsed)
- {
- switch (*begin)
- {
- case '.':
- if (!field_width_parsed)
- {
- result.field_width = 0;
- field_width_parsed = true;
- begin++;
- }
- else
- {
- // the specifier is invalid!
- result.type = INVALID_PRINT;
- }
- break;
- case '*':
- {
- int w = *va_arg(*arguments, int *);
- if (!field_width_parsed)
- {
- result.field_width = w;
- field_width_parsed = true;
- }
- else
- {
- result.field_precision = w;
- field_precision_parsed = true;
- }
- begin++;
- }
- break;
- case '1':
- case '2':
- case '3':
- case '4':
- case '5':
- case '6':
- case '7':
- case '8':
- case '9':
- case '0':
- {
- char *next;
- unsigned long long w = strtoull(begin, &next, 10);
- if (!field_width_parsed)
- {
- result.field_width = (int)w;
- field_width_parsed = true;
- }
- else if (!field_precision_parsed)
- {
- result.field_precision = (int)w;
- field_precision_parsed = true;
- }
- if (next > begin)
- {
- begin = next;
- }
- }
- break;
- default:
- field_width_parsed = true;
- field_precision_parsed = true;
- }
- }
-
- // step 3: check for type width arguments
- switch (*begin)
- {
- case 0: // unexpected eos
- result.type = INVALID_PRINT;
- return result;
- case 'h':
- {
- if (begin[0] == begin[1])
- {
- result.integer_width = BYTE_WIDTH;
- begin += 2;
- }
- else
- {
- result.integer_width = SHORT_WIDTH;
- begin++;
- }
- break;
- }
- case 'l':
- {
- // TODO: deal with LLP64? idk.
- if (begin[0] == begin[1])
- {
- begin += 2;
- }
- else
- {
- begin++;
- }
- result.integer_width = LONG_WIDTH;
- break;
- }
- case 'j':
- // TODO: use INTMAX_T_WIDTH
- result.integer_width = 64;
- begin++;
- break;
- case 'z':
- // TODO: use SIZE_T_WIDTH?
- result.integer_width = 64;
- begin++;
- break;
- case 't':
- // TODO: use PTRDIFF_T_WIDTH?
- result.integer_width = 32;
- begin++;
- break;
- default:
- // there is no width argument to be found.
- result.integer_width = INT_WIDTH;
- break;
- }
-
- // step 4: parse field type
- switch (*begin)
- {
- // unexpected EOS
- case 0:
- result.type = INVALID_PRINT;
- return result;
- case 'c':
- result.type = CHARACTER_PRINT;
- break;
- case 's':
- result.type = STRING_PRINT;
- break;
- case 'd':
- case 'i':
- result.type = INTEGER_PRINT;
- result.flags |= SIGNED_TYPE_FLAG;
- result.integer_base = DEC_BASE;
- break;
- case 'u':
- result.type = INTEGER_PRINT;
- result.integer_base = DEC_BASE;
- break;
- case 'b':
- result.type = INTEGER_PRINT;
- result.integer_base = BIN_BASE;
- break;
- case 'o':
- result.type = INTEGER_PRINT;
- result.integer_base = OCT_BASE;
- break;
- case 'x':
- result.type = INTEGER_PRINT;
- result.integer_base = HEX_BASE;
- break;
- case 'p':
- // TODO: use UINTPTR_T_WIDTH here?
- // pointer type overrides all flags
- // i can do what i want it says "implementation-defined" in the spec
- result.field_precision = 16;
- result.type = INTEGER_PRINT;
- result.integer_base = HEX_BASE;
- result.integer_width = LONG_WIDTH;
- result.flags = ALTERNATE_FORM_FLAG|ZERO_PAD_FLAG;
- break;
- case 'n':
- // all flags are invalid/ignored and the current count will be
- // stored in the value pointed to by the argument
- result.type = COUNT_PRINT;
- result.flags = INVALID_FLAGS;
- result.integer_width = INVALID_WIDTH;
- result.field_width = 0;
- result.field_precision = 0;
- break;
- default:
- // this byte of the specifier _must_ be valid. if not,
- // the procedure to print should not proceed as it might
- // output garbage.
- // TODO: specify somehow in the output that the format is bad?
- result.type = INVALID_PRINT;
- return result;
- }
-
- begin++;
-
- result.length = begin - format;
- return result;
-}
-
-static char *convert_integer(
- uint64_t value,
- unsigned base,
- int zpadding,
- char *buffer,
- size_t bufsz)
-{
- static const char *stringdigits = "0123456789abcdef";
-
- // the string will be built from the lower-to-higher value, and the
- // result pointer will point to the first character of the string in
- // the supplied buffer
-
- // cannot currently work with a base > 16
- if (base > 16)
- {
- return NULL;
- }
-
- // make absolutely sure there are no excess bits
-
- // the string is being built backwards, so the pointer needs to be
- // at the last byte of the string
- char *result = buffer + bufsz - 1;
-
- // result >= buffer condition ensures we don't underflow
-
- do
- {
- *--result = stringdigits[value % base];
- zpadding--;
- value /= base;
- }
- while (value > 0 && result >= buffer);
-
- while (zpadding-- > 0 && result >= buffer)
- {
- *--result = '0';
- }
-
- return result;
-}
-
-static int print_character(
- struct method *m,
- struct specifier *spec,
- va_list *arguments)
-{
- (void)spec;
- // all specifier flags and etc. are ignored.
- return m->write_character(m, va_arg(*arguments, int));
-}
-
-static int print_string(
- struct method *m,
- struct specifier *spec,
- va_list *arguments)
-{
- // TODO: respect field width
- if (spec->integer_width == LONG_WIDTH)
- {
- return m->write_wstring(m, va_arg(*arguments, const wchar_t *));
- }
- return m->write_string(m, va_arg(*arguments, const char *));
-}
-
-static inline bool is_negative(uint64_t value, unsigned width)
-{
- switch (width)
- {
- case BYTE_WIDTH:
- return ((int8_t)value) < 0;
- case SHORT_WIDTH:
- return ((int16_t)value) < 0;
- case INT_WIDTH:
- return ((int32_t)value) < 0;
- case LONG_WIDTH:
- return ((int64_t)value) < 0;
- default:
- return false;
- }
-}
-
-static int print_integer(
- struct method *m,
- struct specifier *spec,
- va_list *arguments)
-{
- // 65 bytes is the maximum length that convert_integer will need
- // i.e. conversion of uintmax_t to binary plus NUL terminator
- // TODO: use UINTMAX_T_WIDTH + 1?
- char buffer[65] = {0};
- char *s;
- bool negative = false;
- uint64_t value = 0;
- int r = 0;
- unsigned zpad = 0;
-
- switch (spec->integer_width)
- {
- case BYTE_WIDTH:
- case SHORT_WIDTH:
- case INT_WIDTH:
- value = va_arg(*arguments, unsigned int);
- break;
- case LONG_WIDTH:
- value = va_arg(*arguments, uint64_t);
- break;
- default:
- return -1;
- }
-
- // check if we need to bother with signs
- if (spec->flags & SIGNED_TYPE_FLAG)
- {
- if ((negative = is_negative(value, spec->integer_width)))
- {
- value = ~value + 1;
- }
-
- if (negative)
- {
- r = m->write_character(m, '-');
- }
-
- else if (!negative && (spec->flags & SIGN_FLAG_MASK))
- {
- if (spec->flags & EXPLICIT_SIGN_FLAG)
- {
- r = m->write_character(m, '+');
- }
- else
- {
- r = m->write_character(m, ' ');
- }
- }
- }
-
- // zero all the unnecessary bits
- value &= (2ULL << (spec->integer_width - 1)) - 1;
-
- switch (spec->integer_base)
- {
- case BIN_BASE:
- if (spec->flags & ALTERNATE_FORM_FLAG)
- {
- r = m->write_string(m, "0b");
- }
- break;
- case OCT_BASE:
- if (spec->flags & ALTERNATE_FORM_FLAG)
- {
- r = m->write_character(m, '0');
- }
- break;
- case HEX_BASE:
- if (spec->flags & ALTERNATE_FORM_FLAG)
- {
- r = m->write_string(m, "0x");
- }
- break;
- default:
- break;
- }
-
- if (spec->flags & ZERO_PAD_FLAG)
- {
- zpad = spec->field_precision;
- }
- s = convert_integer(value, spec->integer_base, zpad, buffer, sizeof(buffer));
-
- if (s)
- {
- m->write_string(m, s);
- }
- else
- {
- m->write_string(m, "(INVALID)");
- r = -1;
- }
-
- return r;
-}
-
-static int printf_internal(
- struct method *m,
- const char *restrict format,
- va_list *arguments)
-{
- int r = 0;
-
- while (*format && !r)
- {
- // case 1: not a format specification
- if (*format != '%')
- {
- r = m->write_character(m, *format++);
- continue;
- }
-
- // case 2: looks like a format specification, but isn't
- else if (*format == '%' && format[0] == format[1])
- {
- r = m->write_character(m, '%');
- format += 2;
- continue;
- }
-
- // case 3: is a format specification. parse it
- struct specifier spec = parse_specifier(++format, arguments);
-
- switch (spec.type)
- {
- case CHARACTER_PRINT:
- r = print_character(m, &spec, arguments);
- break;
- case STRING_PRINT:
- r = print_string(m, &spec, arguments);
- break;
- case INTEGER_PRINT:
- r = print_integer(m, &spec, arguments);
- break;
- default:
- r = m->write_string(m, "(INVALID)");
- return -1;
- }
- format += spec.length;
- }
-
- return r;
-}
-
-static int kfp_write_character(struct method *m, char c)
-{
- kfputc((int)c, (FILE *)m->output);
- m->count++;
- return 0;
-}
-
-static int kfp_write_wcharacter(struct method *m, wchar_t c)
-{
- kfputc((int)c, (FILE *)m->output);
- m->count++;
- return 0;
-}
-
-static int kfp_write_string(struct method *m, const char *c)
-{
- while (*c)
- {
- m->write_character(m, *c++);
- }
- return 0;
-}
-
-static int kfp_write_wstring(struct method *m, const wchar_t *s)
-{
- while (*s)
- {
- m->write_wcharacter(m, *s++);
- }
- return 0;
-}
-
-int kvfprintf(FILE *f, const char *restrict format, va_list arguments)
-{
- struct method m = {
- kfp_write_character,
- kfp_write_wcharacter,
- kfp_write_string,
- kfp_write_wstring,
- (void *)f,
- 0};
- va_list acopy;
- va_copy(acopy, arguments);
- int r = printf_internal(&m, format, &acopy);
- va_end(acopy);
-
- if (!r)
- {
- return m.count;
- }
- else
- {
- return -1;
- }
-}
-
-int kfprintf(FILE *f, const char *restrict format, ...)
-{
- va_list arguments;
- va_start(arguments, format);
-
- int count = kvfprintf(f, format, arguments);
-
- va_end(arguments);
-
- return count;
-}
-
-int kvprintf(const char *restrict format, va_list arguments)
-{
- va_list acopy;
- va_copy(acopy, arguments);
-
- int count = kvfprintf(kstdout, format, arguments);
-
- va_end(acopy);
-
- return count;
-}
-
-int kprintf(const char *restrict format, ...)
-{
- va_list arguments;
- va_start(arguments, format);
-
- int count = kvprintf(format, arguments);
-
- va_end(arguments);
-
- return count;
-}
-
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