Missing files introduced in r244

1 files changed, 465 insertions, 0 deletions

diff --git a/src/punycode.c b/src/punycode.c
new file mode 100644
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--- /dev/null
+++ b/src/punycode.c
@@ -0,0 +1,465 @@
+/*
+punycode.c from RFC 3492
+http://www.nicemice.net/idn/
+Adam M. Costello
+http://www.nicemice.net/amc/
+
+This is ANSI C code (C89) implementing Punycode (RFC 3492).
+
+*/
+
+#include "punycode.h"
+
+/******************/
+/* Implementation */
+
+#include <string.h>
+
+/*** Bootstring parameters for Punycode ***/
+
+enum { base = 36, tmin = 1, tmax = 26, skew = 38, damp = 700,
+  initial_bias = 72, initial_n = 0x80, delimiter = 0x2D
+};
+
+/* basic(cp) tests whether cp is a basic code point: */
+#define basic(cp) ((punycode_uint)(cp) < 0x80)
+
+/* delim(cp) tests whether cp is a delimiter: */
+#define delim(cp) ((cp) == delimiter)
+
+/* decode_digit(cp) returns the numeric value of a basic code */
+/* point (for use in representing integers) in the range 0 to */
+/* base-1, or base if cp is does not represent a value.       */
+
+static punycode_uint decode_digit(punycode_uint cp) {
+  return cp - 48 < 10 ? cp - 22 : cp - 65 < 26 ? cp - 65 : cp - 97 <
+    26 ? cp - 97 : base;
+}
+
+/* encode_digit(d,flag) returns the basic code point whose value      */
+/* (when used for representing integers) is d, which needs to be in   */
+/* the range 0 to base-1.  The lowercase form is used unless flag is  */
+/* nonzero, in which case the uppercase form is used.  The behavior   */
+/* is undefined if flag is nonzero and digit d has no uppercase form. */
+
+static char encode_digit(punycode_uint d, int flag) {
+  return d + 22 + 75 * (d < 26) - ((flag != 0) << 5);
+  /*  0..25 map to ASCII a..z or A..Z */
+  /* 26..35 map to ASCII 0..9         */
+}
+
+/* flagged(bcp) tests whether a basic code point is flagged */
+/* (uppercase).  The behavior is undefined if bcp is not a  */
+/* basic code point.                                        */
+
+#define flagged(bcp) ((punycode_uint)(bcp) - 65 < 26)
+
+/* encode_basic(bcp,flag) forces a basic code point to lowercase */
+/* if flag is zero, uppercase if flag is nonzero, and returns    */
+/* the resulting code point.  The code point is unchanged if it  */
+/* is caseless.  The behavior is undefined if bcp is not a basic */
+/* code point.                                                   */
+
+static char encode_basic(punycode_uint bcp, int flag) {
+  bcp -= (bcp - 97 < 26) << 5;
+  return bcp + ((!flag && (bcp - 65 < 26)) << 5);
+}
+
+/*** Platform-specific constants ***/
+
+/* maxint is the maximum value of a punycode_uint variable: */
+static const punycode_uint maxint = -1;
+
+/* Because maxint is unsigned, -1 becomes the maximum value. */
+
+/*** Bias adaptation function ***/
+
+static punycode_uint adapt(punycode_uint delta, punycode_uint numpoints,
+                           int firsttime) {
+  punycode_uint k;
+
+  delta = firsttime ? delta / damp : delta >> 1;
+  /* delta >> 1 is a faster way of doing delta / 2 */
+  delta += delta / numpoints;
+
+  for(k = 0; delta > ((base - tmin) * tmax) / 2; k += base) {
+    delta /= base - tmin;
+  }
+
+  return k + (base - tmin + 1) * delta / (delta + skew);
+}
+
+/*** Main encode function ***/
+
+enum punycode_status punycode_encode(punycode_uint input_length,
+                                     const punycode_uint input[],
+                                     const unsigned char case_flags[],
+                                     punycode_uint * output_length,
+                                     char output[]) {
+  punycode_uint n, delta, h, b, out, max_out, bias, j, m, q, k, t;
+
+  /* Initialize the state: */
+
+  n = initial_n;
+  delta = out = 0;
+  max_out = *output_length;
+  bias = initial_bias;
+
+  /* Handle the basic code points: */
+  for(j = 0; j < input_length; ++j) {
+    if (basic(input[j])) {
+      if (max_out - out < 2)
+        return punycode_big_output;
+      output[out++] =
+        case_flags ? encode_basic(input[j], case_flags[j]) : input[j];
+    }
+    /* else if (input[j] < n) return punycode_bad_input; */
+    /* (not needed for Punycode with unsigned code points) */
+  }
+
+  h = b = out;
+
+  /* h is the number of code points that have been handled, b is the  */
+  /* number of basic code points, and out is the number of characters */
+  /* that have been output.                                           */
+
+  if (b > 0)
+    output[out++] = delimiter;
+
+  /* Main encoding loop: */
+
+  while(h < input_length) {
+    /* All non-basic code points < n have been     */
+    /* handled already.  Find the next larger one: */
+
+    for(m = maxint, j = 0; j < input_length; ++j) {
+      /* if (basic(input[j])) continue; */
+      /* (not needed for Punycode) */
+      if (input[j] >= n && input[j] < m)
+        m = input[j];
+    }
+
+    /* Increase delta enough to advance the decoder's    */
+    /* <n,i> state to <m,0>, but guard against overflow: */
+
+    if (m - n > (maxint - delta) / (h + 1))
+      return punycode_overflow;
+    delta += (m - n) * (h + 1);
+    n = m;
+
+    for(j = 0; j < input_length; ++j) {
+      /* Punycode does not need to check whether input[j] is basic: */
+      if (input[j] < n /* || basic(input[j]) */ ) {
+        if (++delta == 0)
+          return punycode_overflow;
+      }
+
+      if (input[j] == n) {
+        /* Represent delta as a generalized variable-length integer: */
+
+        for(q = delta, k = base;; k += base) {
+          if (out >= max_out)
+            return punycode_big_output;
+          t = k <= bias /* + tmin */ ? tmin :   /* +tmin not needed */
+            k >= bias + tmax ? tmax : k - bias;
+          if (q < t)
+            break;
+          output[out++] = encode_digit(t + (q - t) % (base - t), 0);
+          q = (q - t) / (base - t);
+        }
+
+        output[out++] = encode_digit(q, case_flags && case_flags[j]);
+        bias = adapt(delta, h + 1, h == b);
+        delta = 0;
+        ++h;
+      }
+    }
+
+    ++delta, ++n;
+  }
+
+  *output_length = out;
+  return punycode_success;
+}
+
+/*** Main decode function ***/
+
+enum punycode_status punycode_decode(punycode_uint input_length,
+                                     const char input[],
+                                     punycode_uint * output_length,
+                                     punycode_uint output[],
+                                     unsigned char case_flags[]) {
+  punycode_uint n, out, i, max_out, bias, b, j, in, oldi, w, k, digit, t;
+
+  /* Initialize the state: */
+
+  n = initial_n;
+  out = i = 0;
+  max_out = *output_length;
+  bias = initial_bias;
+
+  /* Handle the basic code points:  Let b be the number of input code */
+  /* points before the last delimiter, or 0 if there is none, then    */
+  /* copy the first b code points to the output.                      */
+
+  for(b = j = 0; j < input_length; ++j)
+    if (delim(input[j]))
+      b = j;
+  if (b > max_out)
+    return punycode_big_output;
+
+  for(j = 0; j < b; ++j) {
+    if (case_flags)
+      case_flags[out] = flagged(input[j]);
+    if (!basic(input[j]))
+      return punycode_bad_input;
+    output[out++] = input[j];
+  }
+
+  /* Main decoding loop:  Start just after the last delimiter if any  */
+  /* basic code points were copied; start at the beginning otherwise. */
+
+  for(in = b > 0 ? b + 1 : 0; in < input_length; ++out) {
+
+    /* in is the index of the next character to be consumed, and */
+    /* out is the number of code points in the output array.     */
+
+    /* Decode a generalized variable-length integer into delta,  */
+    /* which gets added to i.  The overflow checking is easier   */
+    /* if we increase i as we go, then subtract off its starting */
+    /* value at the end to obtain delta.                         */
+
+    for(oldi = i, w = 1, k = base;; k += base) {
+      if (in >= input_length)
+        return punycode_bad_input;
+      digit = decode_digit(input[in++]);
+      if (digit >= base)
+        return punycode_bad_input;
+      if (digit > (maxint - i) / w)
+        return punycode_overflow;
+      i += digit * w;
+      t = k <= bias /* + tmin */ ? tmin :       /* +tmin not needed */
+        k >= bias + tmax ? tmax : k - bias;
+      if (digit < t)
+        break;
+      if (w > maxint / (base - t))
+        return punycode_overflow;
+      w *= (base - t);
+    }
+
+    bias = adapt(i - oldi, out + 1, oldi == 0);
+
+    /* i was supposed to wrap around from out+1 to 0,   */
+    /* incrementing n each time, so we'll fix that now: */
+
+    if (i / (out + 1) > maxint - n)
+      return punycode_overflow;
+    n += i / (out + 1);
+    i %= (out + 1);
+
+    /* Insert n at position i of the output: */
+
+    /* not needed for Punycode: */
+    /* if (decode_digit(n) <= base) return punycode_invalid_input; */
+    if (out >= max_out)
+      return punycode_big_output;
+
+    if (case_flags) {
+      memmove(case_flags + i + 1, case_flags + i, out - i);
+      /* Case of last character determines uppercase flag: */
+      case_flags[i] = flagged(input[in - 1]);
+    }
+
+    memmove(output + i + 1, output + i, (out - i) * sizeof *output);
+    output[i++] = n;
+  }
+
+  *output_length = out;
+  return punycode_success;
+}
+
+/******************************************************************/
+/* Wrapper for testing (would normally go in a separate .c file): */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/* For testing, we'll just set some compile-time limits rather than */
+/* use malloc(), and set a compile-time option rather than using a  */
+/* command-line option.                                             */
+
+enum {
+  unicode_max_length = 256,
+  ace_max_length = 256
+};
+
+static void usage(char **argv) {
+  fprintf(stderr,
+          "\n" "%s -e reads code points and writes a Punycode string.\n"
+          "%s -d reads a Punycode string and writes code points.\n" "\n"
+          "Input and output are plain text in the native character set.\n"
+          "Code points are in the form u+hex separated by whitespace.\n"
+          "Although the specification allows Punycode strings to contain\n"
+          "any characters from the ASCII repertoire, this test code\n"
+          "supports only the printable characters, and needs the Punycode\n"
+          "string to be followed by a newline.\n"
+          "The case of the u in u+hex is the force-to-uppercase flag.\n",
+          argv[0], argv[0]);
+  exit(EXIT_FAILURE);
+}
+
+static void fail(const char *msg) {
+  fputs(msg, stderr);
+  exit(EXIT_FAILURE);
+}
+
+static const char too_big[] =
+  "input or output is too large, recompile with larger limits\n";
+static const char invalid_input[] = "invalid input\n";
+static const char overflow[] = "arithmetic overflow\n";
+static const char io_error[] = "I/O error\n";
+
+/* The following string is used to convert printable */
+/* characters between ASCII and the native charset:  */
+
+#ifdef PUNYCODE_COSTELLO_RFC3492_INCLUDE_MAIN
+
+static const char print_ascii[] =
+  "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n" "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n"
+  " !\"#$%&'()*+,-./" "0123456789:;<=>?" "@ABCDEFGHIJKLMNO" "PQRSTUVWXYZ[\\]^_"
+  "`abcdefghijklmno" "pqrstuvwxyz{|}~\n";
+
+int main(int argc, char **argv) {
+  enum punycode_status status;
+  int r;
+  unsigned int input_length, output_length, j;
+  unsigned char case_flags[unicode_max_length];
+
+  if (argc != 2)
+    usage(argv);
+  if (argv[1][0] != '-')
+    usage(argv);
+  if (argv[1][2] != 0)
+    usage(argv);
+
+  if (argv[1][1] == 'e') {
+    punycode_uint input[unicode_max_length];
+    unsigned long codept;
+    char output[ace_max_length + 1], uplus[3];
+    int c;
+
+    /* Read the input code points: */
+
+    input_length = 0;
+
+    for(;;) {
+      r = scanf("%2s%lx", uplus, &codept);
+      if (ferror(stdin))
+        fail(io_error);
+
+      if (r == EOF || r == 0)
+        break;
+
+      if (r != 2 || uplus[1] != '+' || codept > (punycode_uint) - 1) {
+        fail(invalid_input);
+      }
+
+      if (input_length == unicode_max_length)
+        fail(too_big);
+
+      if (uplus[0] == 'u')
+        case_flags[input_length] = 0;
+      else if (uplus[0] == 'U')
+        case_flags[input_length] = 1;
+      else
+        fail(invalid_input);
+
+      input[input_length++] = codept;
+    }
+
+    /* Encode: */
+
+    output_length = ace_max_length;
+    status =
+      punycode_encode(input_length, input, case_flags, &output_length, output);
+    if (status == punycode_bad_input)
+      fail(invalid_input);
+    if (status == punycode_big_output)
+      fail(too_big);
+    if (status == punycode_overflow)
+      fail(overflow);
+    assert(status == punycode_success);
+
+    /* Convert to native charset and output: */
+
+    for(j = 0; j < output_length; ++j) {
+      c = output[j];
+      assert(c >= 0 && c <= 127);
+      if (print_ascii[c] == 0)
+        fail(invalid_input);
+      output[j] = print_ascii[c];
+    }
+
+    output[j] = 0;
+    r = puts(output);
+    if (r == EOF)
+      fail(io_error);
+    return EXIT_SUCCESS;
+  }
+
+  if (argv[1][1] == 'd') {
+    char input[ace_max_length + 2], *p, *pp;
+    punycode_uint output[unicode_max_length];
+
+    /* Read the Punycode input string and convert to ASCII: */
+
+    fgets(input, ace_max_length + 2, stdin);
+    if (ferror(stdin))
+      fail(io_error);
+    if (feof(stdin))
+      fail(invalid_input);
+    input_length = strlen(input) - 1;
+    if (input[input_length] != '\n')
+      fail(too_big);
+    input[input_length] = 0;
+
+    for(p = input; *p != 0; ++p) {
+      pp = strchr(print_ascii, *p);
+      if (pp == 0)
+        fail(invalid_input);
+      *p = pp - print_ascii;
+    }
+
+    /* Decode: */
+
+    output_length = unicode_max_length;
+    status =
+      punycode_decode(input_length, input, &output_length, output, case_flags);
+    if (status == punycode_bad_input)
+      fail(invalid_input);
+    if (status == punycode_big_output)
+      fail(too_big);
+    if (status == punycode_overflow)
+      fail(overflow);
+    assert(status == punycode_success);
+
+    /* Output the result: */
+
+    for(j = 0; j < output_length; ++j) {
+      r =
+        printf("%s+%04lX\n", case_flags[j] ? "U" : "u",
+               (unsigned long) output[j]);
+      if (r < 0)
+        fail(io_error);
+    }
+
+    return EXIT_SUCCESS;
+  }
+
+  usage(argv);
+  return EXIT_SUCCESS;          /* not reached, but quiets compiler warning */
+}
+
+#endif