#include "serial.h"
#include "vga.h"
+static void
+vprintf_core (const char *format, va_list args,
+ void (*output) (char, void *), void *aux);
+\f
+/* <string.h> */
+
/* Sets the SIZE bytes in DST to VALUE. */
void *
memset (void *dst_, int value, size_t size)
return 0;
}
+/* Finds and returns the first occurrence of C in STRING, or a
+ null pointer if C does not appear in STRING. If C == '\0'
+ then returns a pointer to the null terminator at the end of
+ STRING. */
+char *
+strchr (const char *string, int c_)
+{
+ char c = c_;
+
+ ASSERT (string != NULL);
+
+ for (;;)
+ if (*string == c)
+ return (char *) string;
+ else if (*string == '\0')
+ return NULL;
+ else
+ string++;
+}
+
/* Copies string SRC to DST. If SRC is longer than SIZE - 1
characters, only SIZE - 1 characters are copied. A null
terminator is always written to DST, unless SIZE is 0.
Returns the length of SRC.
- See http://www.courtesan.com/todd/papers/strlcpy.html for
+ strlcpy() is not in the standard C library, but it is an
+ increasingly popular extension. See
+ http://www.courtesan.com/todd/papers/strlcpy.html for
information on strlcpy(). */
size_t
strlcpy (char *dst, const char *src, size_t size)
return p - string;
}
-/* Finds and returns the first occurrence of C in STRING, or a
- null pointer if C does not appear in STRING. If C == '\0'
- then returns a pointer to the null terminator at the end of
- STRING. */
-char *
-strchr (const char *string, int c_)
+/* If STRING is less than MAXLEN characters in length, returns
+ its actual length. Otherwise, returns MAXLEN. */
+size_t
+strnlen (const char *string, size_t maxlen)
{
- char c = c_;
-
- ASSERT (string != NULL);
+ size_t length;
- for (;;)
- if (*string == c)
- return (char *) string;
- else if (*string == '\0')
- return NULL;
- else
- string++;
+ for (length = 0; string[length] != '\0' && length < maxlen; length++)
+ continue;
+ return length;
}
/* Finds the first differing characters in strings A and B.
*save_ptr = s;
return token;
}
+\f
+/* <stdlib.h> */
+/* Converts a string representation of a signed decimal integer
+ in S into an `int', which is returned. */
int
atoi (const char *s)
{
return value;
}
\f
-static void
-vprintf_core (const char *format, va_list args,
- void (*output) (char, void *), void *aux);
-
-static void
-vprintk_helper (char ch, void *aux UNUSED)
-{
- vga_putc (ch);
- serial_outb (ch);
-}
-
-void
-vprintk (const char *format, va_list args)
-{
- enum intr_level old_level = intr_disable ();
- vprintf_core (format, args, vprintk_helper, NULL);
- intr_set_level (old_level);
-}
-
-void
-printk (const char *format, ...)
-{
- va_list args;
+/* <stdio.h> */
- va_start (args, format);
- vprintk (format, args);
- va_end (args);
-}
-\f
+/* Auxiliary data for vsnprintf_helper(). */
struct vsnprintf_aux
{
- char *p;
- int length;
- int max_length;
+ char *p; /* Current output position. */
+ int length; /* Length of output string. */
+ int max_length; /* Max length of output string. */
};
-static void
-vsnprintf_helper (char ch, void *aux_)
-{
- struct vsnprintf_aux *aux = aux_;
-
- if (aux->length++ < aux->max_length)
- *aux->p++ = ch;
-}
+static void vsnprintf_helper (char, void *);
+/* Like vprintf(), except that output is stored into BUFFER,
+ which must have space for BUF_SIZE characters. Writes at most
+ BUF_SIZE - 1 characters to BUFFER, followed by a null
+ terminator. BUFFER will always be null-terminated unless
+ BUF_SIZE is zero. Returns the number of characters that would
+ have been written to BUFFER, not including a null terminator,
+ had there been enough room. */
int
-vsnprintf (char *buffer, size_t buf_size,
- const char *format, va_list args)
+vsnprintf (char *buffer, size_t buf_size, const char *format, va_list args)
{
+ /* Set up aux data for vsnprintf_helper(). */
struct vsnprintf_aux aux;
aux.p = buffer;
aux.length = 0;
aux.max_length = buf_size > 0 ? buf_size - 1 : 0;
-
+
+ /* Do most of the work. */
vprintf_core (format, args, vsnprintf_helper, &aux);
+ /* Add null terminator. */
if (buf_size > 0)
*aux.p = '\0';
return aux.length;
}
+/* Helper function for vsnprintf(). */
+static void
+vsnprintf_helper (char ch, void *aux_)
+{
+ struct vsnprintf_aux *aux = aux_;
+
+ if (aux->length++ < aux->max_length)
+ *aux->p++ = ch;
+}
+
+/* Like printf(), except that output is stored into BUFFER,
+ which must have space for BUF_SIZE characters. Writes at most
+ BUF_SIZE - 1 characters to BUFFER, followed by a null
+ terminator. BUFFER will always be null-terminated unless
+ BUF_SIZE is zero. Returns the number of characters that would
+ have been written to BUFFER, not including a null terminator,
+ had there been enough room. */
int
-snprintf (char *buffer, size_t buf_size,
- const char *format, ...)
+snprintf (char *buffer, size_t buf_size, const char *format, ...)
{
va_list args;
int retval;
return retval;
}
\f
-/* printf() and friends internals. You do not need to understand
- this code. */
+/* Nonstandard functions. */
+
+static void vprintk_helper (char, void *);
+
+/* Like vprintf(), except that output is written to the system
+ console, which is defined as the video display and the first
+ serial port (at the same time). */
+void
+vprintk (const char *format, va_list args)
+{
+ enum intr_level old_level = intr_disable ();
+ vprintf_core (format, args, vprintk_helper, NULL);
+ intr_set_level (old_level);
+}
+/* Helper function for vprintk(). */
+static void
+vprintk_helper (char ch, void *aux UNUSED)
+{
+ vga_putc (ch);
+ serial_outb (ch);
+}
+
+/* Like printf(), except that output is written to the system
+ console, which is defined as the video display and the first
+ serial port (at the same time). */
+void
+printk (const char *format, ...)
+{
+ va_list args;
+
+ va_start (args, format);
+ vprintk (format, args);
+ va_end (args);
+}
+\f
+/* printf() formatting internals. */
+
+/* A printf() conversion. */
struct printf_conversion
{
+ /* Flags. */
enum
{
- MINUS = 1 << 0,
- PLUS = 1 << 1,
- SPACE = 1 << 2,
- POUND = 1 << 3,
- ZERO = 1 << 4,
- GROUP = 1 << 5
+ MINUS = 1 << 0, /* '-' */
+ PLUS = 1 << 1, /* '+' */
+ SPACE = 1 << 2, /* ' ' */
+ POUND = 1 << 3, /* '#' */
+ ZERO = 1 << 4, /* '0' */
+ GROUP = 1 << 5 /* '\'' */
}
flags;
+ /* Minimum field width. */
int width;
+
+ /* Numeric precision.
+ -1 indicates no precision was specified. */
int precision;
+ /* Type of argument to format. */
enum
{
- CHAR = 1,
- SHORT = 2,
- INT = 3,
- INTMAX = 4,
- LONG = 5,
- LONGLONG = 6,
- PTRDIFFT = 7,
- SIZET = 8
+ CHAR = 1, /* hh */
+ SHORT = 2, /* h */
+ INT = 3, /* (none) */
+ INTMAX = 4, /* j */
+ LONG = 5, /* l */
+ LONGLONG = 6, /* ll */
+ PTRDIFFT = 7, /* t */
+ SIZET = 8 /* z */
}
type;
};
+struct integer_base
+ {
+ int base; /* Base. */
+ const char *digits; /* Collection of digits. */
+ const char *signifier; /* Prefix used with # flag. */
+ int group; /* Number of digits to group with ' flag. */
+ };
+
+static const struct integer_base base_d = {10, "0123456789", "", 3};
+static const struct integer_base base_o = {8, "01234567", "0", 3};
+static const struct integer_base base_x = {16, "0123456789acbdef", "", 4};
+static const struct integer_base base_X = {16, "0123456789ABCDEF", "", 4};
+
+static const char *parse_conversion (const char *format,
+ struct printf_conversion *,
+ va_list *);
+static void format_integer (uintmax_t value, bool negative,
+ const struct integer_base *,
+ const struct printf_conversion *,
+ void (*output) (char, void *), void *aux);
+static void output_dup (char ch, size_t cnt,
+ void (*output) (char, void *), void *aux);
+static void format_string (const char *string, size_t length,
+ struct printf_conversion *,
+ void (*output) (char, void *), void *aux);
+static void printf_core (const char *format,
+ void (*output) (char, void *), void *aux, ...);
+
+static void
+vprintf_core (const char *format, va_list args,
+ void (*output) (char, void *), void *aux)
+{
+ for (; *format != '\0'; format++)
+ {
+ struct printf_conversion c;
+
+ /* Literally copy non-conversions to output. */
+ if (*format != '%')
+ {
+ output (*format, aux);
+ continue;
+ }
+ format++;
+
+ /* %% => %. */
+ if (*format == '%')
+ {
+ output ('%', aux);
+ continue;
+ }
+
+ /* Parse conversion specifiers. */
+ format = parse_conversion (format, &c, &args);
+
+ /* Do conversion. */
+ switch (*format)
+ {
+ case 'd':
+ case 'i':
+ {
+ /* Signed integer conversions. */
+ intmax_t value;
+
+ switch (c.type)
+ {
+ case CHAR:
+ value = (signed char) va_arg (args, int);
+ break;
+ case SHORT:
+ value = (short) va_arg (args, int);
+ break;
+ case INT:
+ value = va_arg (args, int);
+ break;
+ case LONG:
+ value = va_arg (args, long);
+ break;
+ case LONGLONG:
+ value = va_arg (args, long long);
+ break;
+ case PTRDIFFT:
+ value = va_arg (args, ptrdiff_t);
+ break;
+ case SIZET:
+ value = va_arg (args, size_t);
+ break;
+ default:
+ NOT_REACHED ();
+ }
+
+ format_integer (value < 0 ? -value : value,
+ value < 0, &base_d, &c, output, aux);
+ }
+ break;
+
+ case 'o':
+ case 'u':
+ case 'x':
+ case 'X':
+ {
+ /* Unsigned integer conversions. */
+ uintmax_t value;
+ const struct integer_base *b;
+
+ switch (c.type)
+ {
+ case CHAR:
+ value = (unsigned char) va_arg (args, unsigned);
+ break;
+ case SHORT:
+ value = (unsigned short) va_arg (args, unsigned);
+ break;
+ case INT:
+ value = va_arg (args, unsigned);
+ break;
+ case LONG:
+ value = va_arg (args, unsigned long);
+ break;
+ case LONGLONG:
+ value = va_arg (args, unsigned long long);
+ break;
+ case PTRDIFFT:
+ value = va_arg (args, ptrdiff_t);
+ break;
+ case SIZET:
+ value = va_arg (args, size_t);
+ break;
+ default:
+ NOT_REACHED ();
+ }
+
+ switch (*format)
+ {
+ case 'o': b = &base_o; break;
+ case 'u': b = &base_d; break;
+ case 'x': b = &base_x; break;
+ case 'X': b = &base_X; break;
+ default: NOT_REACHED ();
+ }
+
+ format_integer (value, false, b, &c, output, aux);
+ }
+ break;
+
+ case 'c':
+ {
+ /* Treat character as single-character string. */
+ char ch = va_arg (args, int);
+ format_string (&ch, 1, &c, output, aux);
+ }
+ break;
+
+ case 's':
+ {
+ /* String conversion. */
+ const char *s = va_arg (args, char *);
+ if (s == NULL)
+ s = "(null)";
+
+ /* Limit string length according to precision.
+ Note: if c.precision == -1 then strnlen() will get
+ SIZE_MAX for MAXLEN, which is just what we want. */
+ format_string (s, strnlen (s, c.precision), &c, output, aux);
+ }
+ break;
+
+ case 'p':
+ {
+ /* Pointer conversion.
+ Format non-null pointers as %#x. */
+ void *p = va_arg (args, void *);
+
+ c.flags = POUND;
+ if (p != NULL)
+ format_integer ((uintptr_t) p, false, &base_x, &c, output, aux);
+ else
+ format_string ("(nil)", 5, &c, output, aux);
+ }
+ break;
+
+ case 'f':
+ case 'e':
+ case 'E':
+ case 'g':
+ case 'G':
+ case 'n':
+ /* We don't support floating-point arithmetic,
+ and %n can be part of a security hole. */
+ printf_core ("<<no %%%c in kernel>>", output, aux, *format);
+ break;
+
+ default:
+ printf_core ("<<no %%%c conversion>>", output, aux, *format);
+ break;
+ }
+ }
+}
+
+/* Parses conversion option characters starting at FORMAT and
+ initializes C appropriately. Returns the character in FORMAT
+ that indicates the conversion (e.g. the `d' in `%d'). Uses
+ *ARGS for `*' field widths and precisions. */
static const char *
parse_conversion (const char *format, struct printf_conversion *c,
va_list *args)
c->type = LONG;
break;
- case 'L':
- case 'q':
- c->type = LONGLONG;
- break;
-
case 't':
c->type = PTRDIFFT;
break;
case 'z':
- case 'Z':
c->type = SIZET;
break;
return format;
}
+/* Performs an integer conversion, writing output to OUTPUT with
+ auxiliary data AUX. The integer converted has absolute value
+ VALUE. If NEGATIVE is true the value is negative, otherwise
+ positive. The output will use the given DIGITS, with
+ strlen(DIGITS) indicating the output base. Details of the
+ conversion are in C. */
static void
-output_dup (char ch, size_t cnt, void (*output) (char, void *), void *aux)
-{
- while (cnt-- > 0)
- output (ch, aux);
-}
-
-static void
-printf_integer (uintmax_t value, bool negative, const char *digits,
- struct printf_conversion *c,
+format_integer (uintmax_t value, bool negative, const struct integer_base *b,
+ const struct printf_conversion *c,
void (*output) (char, void *), void *aux)
-
{
- char buf[64], *cp;
- int base;
- const char *base_name;
- int pad_cnt, group_cnt;
-
- base = strlen (digits);
+ char buf[64], *cp; /* Buffer and current position. */
+ const char *signifier; /* b->signifier or "". */
+ int precision; /* Rendered precision. */
+ int pad_cnt; /* # of pad characters to fill field width. */
+ int group_cnt; /* # of digits grouped so far. */
/* Accumulate digits into buffer.
This algorithm produces digits in reverse order, so later we
group_cnt = 0;
while (value > 0)
{
- if ((c->flags & GROUP) && group_cnt++ == 3)
+ if ((c->flags & GROUP) && group_cnt++ == b->group)
{
*cp++ = ',';
group_cnt = 0;
}
- *cp++ = digits[value % base];
- value /= base;
+ *cp++ = b->digits[value % b->base];
+ value /= b->base;
}
/* Append enough zeros to match precision.
- If precision is 0, then a value of zero is rendered as a
- null string. Otherwise at least one digit is presented. */
- if (c->precision < 0)
- c->precision = 1;
- while (cp - buf < c->precision && cp - buf < (int) sizeof buf - 8)
+ If requested precision is 0, then a value of zero is
+ rendered as a null string, otherwise as "0". */
+ precision = c->precision < 0 ? 1 : c->precision;
+ if (precision < 0)
+ precision = 1;
+ while (cp - buf < precision && cp - buf < (int) sizeof buf - 8)
*cp++ = '0';
/* Append sign. */
else if (negative)
*cp++ = '-';
- /* Get name of base. */
- base_name = "";
- if (c->flags & POUND)
- {
- if (base == 8)
- base_name = "0";
- else if (base == 16)
- base_name = digits[0xa] == 'a' ? "0x" : "0X";
- }
-
/* Calculate number of pad characters to fill field width. */
- pad_cnt = c->width - (cp - buf) - strlen (base_name);
+ signifier = c->flags & POUND ? b->signifier : "";
+ pad_cnt = c->width - (cp - buf) - strlen (signifier);
if (pad_cnt < 0)
pad_cnt = 0;
/* Do output. */
if ((c->flags & (MINUS | ZERO)) == 0)
output_dup (' ', pad_cnt, output, aux);
- while (*base_name != '\0')
- output (*base_name++, aux);
+ while (*signifier != '\0')
+ output (*signifier++, aux);
if (c->flags & ZERO)
output_dup ('0', pad_cnt, output, aux);
while (cp > buf)
output_dup (' ', pad_cnt, output, aux);
}
+/* Writes CH to OUTPUT with auxiliary data AUX, CNT times. */
static void
-printf_string (const char *string, size_t length,
+output_dup (char ch, size_t cnt, void (*output) (char, void *), void *aux)
+{
+ while (cnt-- > 0)
+ output (ch, aux);
+}
+
+/* Formats the LENGTH characters starting at STRING according to
+ the conversion specified in C. Writes output to OUTPUT with
+ auxiliary data AUX. */
+static void
+format_string (const char *string, size_t length,
struct printf_conversion *c,
void (*output) (char, void *), void *aux)
{
output_dup (' ', c->width - 1, output, aux);
}
+/* Wrapper for vprintf_core() that converts varargs into a
+ va_list. */
static void
printf_core (const char *format,
void (*output) (char, void *), void *aux, ...)
vprintf_core (format, args, output, aux);
va_end (args);
}
-
-static void
-vprintf_core (const char *format, va_list args,
- void (*output) (char, void *), void *aux)
-{
- for (; *format != '\0'; format++)
- {
- struct printf_conversion c;
-
- /* Literally copy non-conversions to output. */
- if (*format != '%')
- {
- output (*format, aux);
- continue;
- }
- format++;
-
- /* %% => %. */
- if (*format == '%')
- {
- output ('%', aux);
- continue;
- }
-
- format = parse_conversion (format, &c, &args);
- switch (*format)
- {
- case 'd':
- case 'i':
- {
- intmax_t value;
- uintmax_t abs_value;
- bool negative = false;
-
- switch (c.type)
- {
- case CHAR:
- value = (signed char) va_arg (args, int);
- break;
- case SHORT:
- value = (short) va_arg (args, int);
- break;
- case INT:
- value = va_arg (args, int);
- break;
- case LONG:
- value = va_arg (args, long);
- break;
- case LONGLONG:
- value = va_arg (args, long long);
- break;
- case PTRDIFFT:
- value = va_arg (args, ptrdiff_t);
- break;
- case SIZET:
- value = va_arg (args, size_t);
- break;
- default:
- NOT_REACHED ();
- }
-
- if (value < 0)
- {
- negative = true;
- abs_value = -value;
- }
- else
- abs_value = value;
-
- printf_integer (abs_value, negative, "0123456789",
- &c, output, aux);
- }
- break;
-
- case 'o':
- case 'u':
- case 'x':
- case 'X':
- {
- uintmax_t value;
- const char *digits;
-
- switch (c.type)
- {
- case CHAR:
- value = (unsigned char) va_arg (args, unsigned);
- break;
- case SHORT:
- value = (unsigned short) va_arg (args, unsigned);
- break;
- case INT:
- value = va_arg (args, unsigned);
- break;
- case LONG:
- value = va_arg (args, unsigned long);
- break;
- case LONGLONG:
- value = va_arg (args, unsigned long long);
- break;
- case PTRDIFFT:
- value = va_arg (args, ptrdiff_t);
- break;
- case SIZET:
- value = va_arg (args, size_t);
- break;
- default:
- NOT_REACHED ();
- }
-
- switch (*format)
- {
- case 'o':
- digits = "01234567";
- break;
- case 'u':
- digits = "0123456789";
- break;
- case 'x':
- digits = "0123456789abcdef";
- break;
- case 'X':
- digits = "0123456789ABCDEF";
- break;
- default:
- NOT_REACHED ();
- }
-
- printf_integer (value, false, digits, &c, output, aux);
- }
- break;
-
- case 'c':
- {
- char ch = va_arg (args, int);
- printf_string (&ch, 1, &c, output, aux);
- }
- break;
-
- case 's':
- {
- const char *s;
- size_t length;
-
- s = va_arg (args, char *);
- if (s == NULL)
- s = "(null)";
-
- if (c.precision >= 0)
- {
- const char *zero = memchr (s, '\0', c.precision);
- if (zero != NULL)
- length = zero - s;
- else
- length = c.precision;
- }
- else
- length = strlen (s);
-
- printf_string (s, length, &c, output, aux);
- }
- break;
-
- case 'p':
- {
- void *p = va_arg (args, void *);
-
- c.flags = POUND;
- if (p != NULL)
- printf_integer ((uintptr_t) p,
- false, "0123456789abcdef", &c,
- output, aux);
- else
- printf_string ("(nil)", 5, &c, output, aux);
- }
- break;
-
- case 'f':
- case 'e':
- case 'E':
- case 'g':
- case 'G':
- case 'n':
- printf_core ("<<no %%%c in kernel>>", output, aux, *format);
- break;
-
- default:
- printf_core ("<<no %%%c conversion>>", output, aux, *format);
- break;
- }
- }
-}
\f
+/* Dumps the SIZE bytes in BUFFER to the console as hex bytes
+ arranged 16 per line. If ASCII is true then the corresponding
+ ASCII characters are also rendered alongside. */
void
hex_dump (const void *buffer, size_t size, bool ascii)
{
- const size_t n_per_line = 16;
- const uint8_t *p = buffer;
- size_t ofs = 0;
+ const size_t n_per_line = 16; /* Maximum bytes per line. */
+ size_t n; /* Number of bytes in this line. */
+ const uint8_t *p; /* Start of current line in buffer. */
- while (size > 0)
+ for (p = buffer; p < (uint8_t *) buffer + size; p += n)
{
- size_t n, i;
+ size_t i;
- printk ("%08zx", ofs);
- n = size >= n_per_line ? n_per_line : size;
+ /* Number of bytes on this line. */
+ n = (uint8_t *) (buffer + size) - p;
+ if (n > n_per_line)
+ n = n_per_line;
+
+ /* Print line. */
for (i = 0; i < n; i++)
printk ("%c%02x", i == n_per_line / 2 ? '-' : ' ', (unsigned) p[i]);
-
if (ascii)
{
for (; i < n_per_line; i++)
printk ("|");
}
printk ("\n");
-
- p += n;
- ofs += n;
- size -= n;
}
}
projects / pintos-anon / commitdiff