--- /dev/null
+#include <ctype.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+
+/* Auxiliary data for vsnprintf_helper(). */
+struct vsnprintf_aux
+ {
+ char *p; /* Current output position. */
+ int length; /* Length of output string. */
+ int max_length; /* Max length of output string. */
+ };
+
+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)
+{
+ /* 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 (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, ...)
+{
+ va_list args;
+ int retval;
+
+ va_start (args, format);
+ retval = vsnprintf (buffer, buf_size, format, args);
+ va_end (args);
+
+ return retval;
+}
+
+/* Writes formatted output to the console.
+ In the kernel, the console is both the video display and first
+ serial port.
+ In userspace, the console is file descriptor 1.
+*/
+int
+printf (const char *format, ...)
+{
+ va_list args;
+ int retval;
+
+ va_start (args, format);
+ retval = vprintf (format, args);
+ va_end (args);
+
+ return retval;
+}
+\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, /* '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, /* 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, "0123456789abcdef", "0x", 4};
+static const struct integer_base base_X = {16, "0123456789ABCDEF", "0X", 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);
+
+void
+__vprintf (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 ("<<no %%%c in kernel>>", output, aux, *format);
+ break;
+
+ default:
+ __printf ("<<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)
+{
+ /* Parse flag characters. */
+ c->flags = 0;
+ for (;;)
+ {
+ switch (*format++)
+ {
+ case '-':
+ c->flags |= MINUS;
+ break;
+ case '+':
+ c->flags |= PLUS;
+ break;
+ case ' ':
+ c->flags |= SPACE;
+ break;
+ case '#':
+ c->flags |= POUND;
+ break;
+ case '0':
+ c->flags |= ZERO;
+ break;
+ case '\'':
+ c->flags |= GROUP;
+ break;
+ default:
+ format--;
+ goto not_a_flag;
+ }
+ }
+ not_a_flag:
+ if (c->flags & MINUS)
+ c->flags &= ~ZERO;
+ if (c->flags & PLUS)
+ c->flags &= ~SPACE;
+
+ /* Parse field width. */
+ c->width = 0;
+ if (*format == '*')
+ {
+ format++;
+ c->width = va_arg (*args, int);
+ }
+ else
+ {
+ for (; isdigit (*format); format++)
+ c->width = c->width * 10 + *format - '0';
+ }
+ if (c->width < 0)
+ {
+ c->width = -c->width;
+ c->flags |= MINUS;
+ }
+
+ /* Parse precision. */
+ c->precision = -1;
+ if (*format == '.')
+ {
+ format++;
+ if (*format == '*')
+ {
+ format++;
+ c->precision = va_arg (*args, int);
+ }
+ else
+ {
+ c->precision = 0;
+ for (; isdigit (*format); format++)
+ c->precision = c->precision * 10 + *format - '0';
+ }
+ if (c->precision < 0)
+ c->precision = -1;
+ }
+ if (c->precision >= 0)
+ c->flags &= ~ZERO;
+
+ /* Parse type. */
+ c->type = INT;
+ switch (*format++)
+ {
+ case 'h':
+ if (*format == 'h')
+ {
+ format++;
+ c->type = CHAR;
+ }
+ else
+ c->type = SHORT;
+ break;
+
+ case 'j':
+ c->type = INTMAX;
+ break;
+
+ case 'l':
+ if (*format == 'l')
+ {
+ format++;
+ c->type = LONGLONG;
+ }
+ else
+ c->type = LONG;
+ break;
+
+ case 't':
+ c->type = PTRDIFFT;
+ break;
+
+ case 'z':
+ c->type = SIZET;
+ break;
+
+ default:
+ format--;
+ 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
+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; /* 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
+ will output the buffer's content in reverse. This is also
+ the reason that later we append zeros and the sign. */
+ cp = buf;
+ group_cnt = 0;
+ while (value > 0)
+ {
+ if ((c->flags & GROUP) && group_cnt++ == b->group)
+ {
+ *cp++ = ',';
+ group_cnt = 0;
+ }
+ *cp++ = b->digits[value % b->base];
+ value /= b->base;
+ }
+
+ /* Append enough zeros to match precision.
+ 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. */
+ if (c->flags & PLUS)
+ *cp++ = negative ? '-' : '+';
+ else if (c->flags & SPACE)
+ *cp++ = negative ? '-' : ' ';
+ else if (negative)
+ *cp++ = '-';
+
+ /* Calculate number of pad characters to fill field width. */
+ 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 (*signifier != '\0')
+ output (*signifier++, aux);
+ if (c->flags & ZERO)
+ output_dup ('0', pad_cnt, output, aux);
+ while (cp > buf)
+ output (*--cp, aux);
+ if (c->flags & MINUS)
+ output_dup (' ', pad_cnt, output, aux);
+}
+
+/* Writes CH to OUTPUT with auxiliary data AUX, CNT times. */
+static void
+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)
+{
+ if (c->width > 1 && (c->flags & MINUS) == 0)
+ output_dup (' ', c->width - 1, output, aux);
+ while (length-- > 0)
+ output (*string++, aux);
+ if (c->width > 1 && (c->flags & MINUS) != 0)
+ output_dup (' ', c->width - 1, output, aux);
+}
+
+/* Wrapper for __vprintf() that converts varargs into a
+ va_list. */
+void
+__printf (const char *format,
+ void (*output) (char, void *), void *aux, ...)
+{
+ va_list args;
+
+ va_start (args, aux);
+ __vprintf (format, args, output, aux);
+ va_end (args);
+}
+
+/* Writes string S to the console, followed by a new-line
+ character. */
+int
+puts (const char *s)
+{
+ while (*s != '\0')
+ putchar (*s++);
+ putchar ('\n');
+ return 0;
+}
+\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; /* Maximum bytes per line. */
+ size_t n; /* Number of bytes in this line. */
+ const uint8_t *p; /* Start of current line in buffer. */
+
+ for (p = buffer; p < (uint8_t *) buffer + size; p += n)
+ {
+ size_t i;
+
+ /* 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++)
+ printf ("%c%02x", i == n_per_line / 2 ? '-' : ' ', (unsigned) p[i]);
+ if (ascii)
+ {
+ for (; i < n_per_line; i++)
+ printf (" ");
+ printf (" |");
+ for (i = 0; i < n; i++)
+ printf ("%c", isprint (p[i]) ? p[i] : '.');
+ for (; i < n_per_line; i++)
+ printf (" ");
+ printf ("|");
+ }
+ printf ("\n");
+ }
+}
projects / pintos-anon / blobdiff