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  1. /*
  2.  * Copyright (c) 2005 Martin Decky
  3.  * Copyright (c) 2008 Jiri Svoboda
  4.  * All rights reserved.
  5.  *
  6.  * Redistribution and use in source and binary forms, with or without
  7.  * modification, are permitted provided that the following conditions
  8.  * are met:
  9.  *
  10.  * - Redistributions of source code must retain the above copyright
  11.  *   notice, this list of conditions and the following disclaimer.
  12.  * - Redistributions in binary form must reproduce the above copyright
  13.  *   notice, this list of conditions and the following disclaimer in the
  14.  *   documentation and/or other materials provided with the distribution.
  15.  * - The name of the author may not be used to endorse or promote products
  16.  *   derived from this software without specific prior written permission.
  17.  *
  18.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28.  */
  29.  
  30. /** @addtogroup libc
  31.  * @{
  32.  */
  33. /** @file
  34.  */
  35.  
  36. #include <string.h>
  37. #include <stdlib.h>
  38. #include <limits.h>
  39. #include <ctype.h>
  40. #include <malloc.h>
  41. #include <errno.h>
  42. #include <align.h>
  43. #include <mem.h>
  44. #include <string.h>
  45.  
  46. /** Byte mask consisting of lowest @n bits (out of 8) */
  47. #define LO_MASK_8(n)  ((uint8_t) ((1 << (n)) - 1))
  48.  
  49. /** Byte mask consisting of lowest @n bits (out of 32) */
  50. #define LO_MASK_32(n)  ((uint32_t) ((1 << (n)) - 1))
  51.  
  52. /** Byte mask consisting of highest @n bits (out of 8) */
  53. #define HI_MASK_8(n)  (~LO_MASK_8(8 - (n)))
  54.  
  55. /** Number of data bits in a UTF-8 continuation byte */
  56. #define CONT_BITS  6
  57.  
  58. /** Decode a single character from a string.
  59.  *
  60.  * Decode a single character from a string of size @a size. Decoding starts
  61.  * at @a offset and this offset is moved to the beginning of the next
  62.  * character. In case of decoding error, offset generally advances at least
  63.  * by one. However, offset is never moved beyond size.
  64.  *
  65.  * @param str    String (not necessarily NULL-terminated).
  66.  * @param offset Byte offset in string where to start decoding.
  67.  * @param size   Size of the string (in bytes).
  68.  *
  69.  * @return Value of decoded character, U_SPECIAL on decoding error or
  70.  *         NULL if attempt to decode beyond @a size.
  71.  *
  72.  */
  73. wchar_t str_decode(const char *str, size_t *offset, size_t size)
  74. {
  75.     if (*offset + 1 > size)
  76.         return 0;
  77.    
  78.     /* First byte read from string */
  79.     uint8_t b0 = (uint8_t) str[(*offset)++];
  80.    
  81.     /* Determine code length */
  82.    
  83.     unsigned int b0_bits;  /* Data bits in first byte */
  84.     unsigned int cbytes;   /* Number of continuation bytes */
  85.    
  86.     if ((b0 & 0x80) == 0) {
  87.         /* 0xxxxxxx (Plain ASCII) */
  88.         b0_bits = 7;
  89.         cbytes = 0;
  90.     } else if ((b0 & 0xe0) == 0xc0) {
  91.         /* 110xxxxx 10xxxxxx */
  92.         b0_bits = 5;
  93.         cbytes = 1;
  94.     } else if ((b0 & 0xf0) == 0xe0) {
  95.         /* 1110xxxx 10xxxxxx 10xxxxxx */
  96.         b0_bits = 4;
  97.         cbytes = 2;
  98.     } else if ((b0 & 0xf8) == 0xf0) {
  99.         /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
  100.         b0_bits = 3;
  101.         cbytes = 3;
  102.     } else {
  103.         /* 10xxxxxx -- unexpected continuation byte */
  104.         return U_SPECIAL;
  105.     }
  106.    
  107.     if (*offset + cbytes > size)
  108.         return U_SPECIAL;
  109.    
  110.     wchar_t ch = b0 & LO_MASK_8(b0_bits);
  111.    
  112.     /* Decode continuation bytes */
  113.     while (cbytes > 0) {
  114.         uint8_t b = (uint8_t) str[(*offset)++];
  115.        
  116.         /* Must be 10xxxxxx */
  117.         if ((b & 0xc0) != 0x80)
  118.             return U_SPECIAL;
  119.        
  120.         /* Shift data bits to ch */
  121.         ch = (ch << CONT_BITS) | (wchar_t) (b & LO_MASK_8(CONT_BITS));
  122.         cbytes--;
  123.     }
  124.    
  125.     return ch;
  126. }
  127.  
  128. /** Encode a single character to string representation.
  129.  *
  130.  * Encode a single character to string representation (i.e. UTF-8) and store
  131.  * it into a buffer at @a offset. Encoding starts at @a offset and this offset
  132.  * is moved to the position where the next character can be written to.
  133.  *
  134.  * @param ch     Input character.
  135.  * @param str    Output buffer.
  136.  * @param offset Byte offset where to start writing.
  137.  * @param size   Size of the output buffer (in bytes).
  138.  *
  139.  * @return EOK if the character was encoded successfully, EOVERFLOW if there
  140.  *     was not enough space in the output buffer or EINVAL if the character
  141.  *     code was invalid.
  142.  */
  143. int chr_encode(const wchar_t ch, char *str, size_t *offset, size_t size)
  144. {
  145.     if (*offset >= size)
  146.         return EOVERFLOW;
  147.    
  148.     if (!chr_check(ch))
  149.         return EINVAL;
  150.    
  151.     /* Unsigned version of ch (bit operations should only be done
  152.        on unsigned types). */
  153.     uint32_t cc = (uint32_t) ch;
  154.    
  155.     /* Determine how many continuation bytes are needed */
  156.    
  157.     unsigned int b0_bits;  /* Data bits in first byte */
  158.     unsigned int cbytes;   /* Number of continuation bytes */
  159.    
  160.     if ((cc & ~LO_MASK_32(7)) == 0) {
  161.         b0_bits = 7;
  162.         cbytes = 0;
  163.     } else if ((cc & ~LO_MASK_32(11)) == 0) {
  164.         b0_bits = 5;
  165.         cbytes = 1;
  166.     } else if ((cc & ~LO_MASK_32(16)) == 0) {
  167.         b0_bits = 4;
  168.         cbytes = 2;
  169.     } else if ((cc & ~LO_MASK_32(21)) == 0) {
  170.         b0_bits = 3;
  171.         cbytes = 3;
  172.     } else {
  173.         /* Codes longer than 21 bits are not supported */
  174.         return EINVAL;
  175.     }
  176.    
  177.     /* Check for available space in buffer */
  178.     if (*offset + cbytes >= size)
  179.         return EOVERFLOW;
  180.    
  181.     /* Encode continuation bytes */
  182.     unsigned int i;
  183.     for (i = cbytes; i > 0; i--) {
  184.         str[*offset + i] = 0x80 | (cc & LO_MASK_32(CONT_BITS));
  185.         cc = cc >> CONT_BITS;
  186.     }
  187.    
  188.     /* Encode first byte */
  189.     str[*offset] = (cc & LO_MASK_32(b0_bits)) | HI_MASK_8(8 - b0_bits - 1);
  190.    
  191.     /* Advance offset */
  192.     *offset += cbytes + 1;
  193.    
  194.     return EOK;
  195. }
  196.  
  197. /** Get size of string.
  198.  *
  199.  * Get the number of bytes which are used by the string @a str (excluding the
  200.  * NULL-terminator).
  201.  *
  202.  * @param str String to consider.
  203.  *
  204.  * @return Number of bytes used by the string
  205.  *
  206.  */
  207. size_t str_size(const char *str)
  208. {
  209.     size_t size = 0;
  210.    
  211.     while (*str++ != 0)
  212.         size++;
  213.    
  214.     return size;
  215. }
  216.  
  217. /** Get size of wide string.
  218.  *
  219.  * Get the number of bytes which are used by the wide string @a str (excluding the
  220.  * NULL-terminator).
  221.  *
  222.  * @param str Wide string to consider.
  223.  *
  224.  * @return Number of bytes used by the wide string
  225.  *
  226.  */
  227. size_t wstr_size(const wchar_t *str)
  228. {
  229.     return (wstr_length(str) * sizeof(wchar_t));
  230. }
  231.  
  232. /** Get size of string with length limit.
  233.  *
  234.  * Get the number of bytes which are used by up to @a max_len first
  235.  * characters in the string @a str. If @a max_len is greater than
  236.  * the length of @a str, the entire string is measured (excluding the
  237.  * NULL-terminator).
  238.  *
  239.  * @param str     String to consider.
  240.  * @param max_len Maximum number of characters to measure.
  241.  *
  242.  * @return Number of bytes used by the characters.
  243.  *
  244.  */
  245. size_t str_lsize(const char *str, count_t max_len)
  246. {
  247.     count_t len = 0;
  248.     size_t offset = 0;
  249.    
  250.     while (len < max_len) {
  251.         if (str_decode(str, &offset, STR_NO_LIMIT) == 0)
  252.             break;
  253.        
  254.         len++;
  255.     }
  256.    
  257.     return offset;
  258. }
  259.  
  260. /** Get size of wide string with length limit.
  261.  *
  262.  * Get the number of bytes which are used by up to @a max_len first
  263.  * wide characters in the wide string @a str. If @a max_len is greater than
  264.  * the length of @a str, the entire wide string is measured (excluding the
  265.  * NULL-terminator).
  266.  *
  267.  * @param str     Wide string to consider.
  268.  * @param max_len Maximum number of wide characters to measure.
  269.  *
  270.  * @return Number of bytes used by the wide characters.
  271.  *
  272.  */
  273. size_t wstr_lsize(const wchar_t *str, count_t max_len)
  274. {
  275.     return (wstr_nlength(str, max_len * sizeof(wchar_t)) * sizeof(wchar_t));
  276. }
  277.  
  278. /** Get number of characters in a string.
  279.  *
  280.  * @param str NULL-terminated string.
  281.  *
  282.  * @return Number of characters in string.
  283.  *
  284.  */
  285. count_t str_length(const char *str)
  286. {
  287.     count_t len = 0;
  288.     size_t offset = 0;
  289.    
  290.     while (str_decode(str, &offset, STR_NO_LIMIT) != 0)
  291.         len++;
  292.    
  293.     return len;
  294. }
  295.  
  296. /** Get number of characters in a wide string.
  297.  *
  298.  * @param str NULL-terminated wide string.
  299.  *
  300.  * @return Number of characters in @a str.
  301.  *
  302.  */
  303. count_t wstr_length(const wchar_t *wstr)
  304. {
  305.     count_t len = 0;
  306.    
  307.     while (*wstr++ != 0)
  308.         len++;
  309.    
  310.     return len;
  311. }
  312.  
  313. /** Get number of characters in a string with size limit.
  314.  *
  315.  * @param str  NULL-terminated string.
  316.  * @param size Maximum number of bytes to consider.
  317.  *
  318.  * @return Number of characters in string.
  319.  *
  320.  */
  321. count_t str_nlength(const char *str, size_t size)
  322. {
  323.     count_t len = 0;
  324.     size_t offset = 0;
  325.    
  326.     while (str_decode(str, &offset, size) != 0)
  327.         len++;
  328.    
  329.     return len;
  330. }
  331.  
  332. /** Get number of characters in a string with size limit.
  333.  *
  334.  * @param str  NULL-terminated string.
  335.  * @param size Maximum number of bytes to consider.
  336.  *
  337.  * @return Number of characters in string.
  338.  *
  339.  */
  340. count_t wstr_nlength(const wchar_t *str, size_t size)
  341. {
  342.     count_t len = 0;
  343.     count_t limit = ALIGN_DOWN(size, sizeof(wchar_t));
  344.     count_t offset = 0;
  345.    
  346.     while ((offset < limit) && (*str++ != 0)) {
  347.         len++;
  348.         offset += sizeof(wchar_t);
  349.     }
  350.    
  351.     return len;
  352. }
  353.  
  354. /** Check whether character is plain ASCII.
  355.  *
  356.  * @return True if character is plain ASCII.
  357.  *
  358.  */
  359. bool ascii_check(wchar_t ch)
  360. {
  361.     if ((ch >= 0) && (ch <= 127))
  362.         return true;
  363.    
  364.     return false;
  365. }
  366.  
  367. /** Check whether character is valid
  368.  *
  369.  * @return True if character is a valid Unicode code point.
  370.  *
  371.  */
  372. bool chr_check(wchar_t ch)
  373. {
  374.     if ((ch >= 0) && (ch <= 1114111))
  375.         return true;
  376.    
  377.     return false;
  378. }
  379.  
  380. /** Compare two NULL terminated strings.
  381.  *
  382.  * Do a char-by-char comparison of two NULL-terminated strings.
  383.  * The strings are considered equal iff they consist of the same
  384.  * characters on the minimum of their lengths.
  385.  *
  386.  * @param s1 First string to compare.
  387.  * @param s2 Second string to compare.
  388.  *
  389.  * @return 0 if the strings are equal, -1 if first is smaller,
  390.  *         1 if second smaller.
  391.  *
  392.  */
  393. int str_cmp(const char *s1, const char *s2)
  394. {
  395.     wchar_t c1 = 0;
  396.     wchar_t c2 = 0;
  397.    
  398.     size_t off1 = 0;
  399.     size_t off2 = 0;
  400.  
  401.     while (true) {
  402.         c1 = str_decode(s1, &off1, STR_NO_LIMIT);
  403.         c2 = str_decode(s2, &off2, STR_NO_LIMIT);
  404.  
  405.         if (c1 < c2)
  406.             return -1;
  407.        
  408.         if (c1 > c2)
  409.             return 1;
  410.  
  411.         if (c1 == 0 || c2 == 0)
  412.             break;     
  413.     }
  414.  
  415.     return 0;
  416. }
  417.  
  418. /** Compare two NULL terminated strings with length limit.
  419.  *
  420.  * Do a char-by-char comparison of two NULL-terminated strings.
  421.  * The strings are considered equal iff they consist of the same
  422.  * characters on the minimum of their lengths and the length limit.
  423.  *
  424.  * @param s1      First string to compare.
  425.  * @param s2      Second string to compare.
  426.  * @param max_len Maximum number of characters to consider.
  427.  *
  428.  * @return 0 if the strings are equal, -1 if first is smaller,
  429.  *         1 if second smaller.
  430.  *
  431.  */
  432. int str_lcmp(const char *s1, const char *s2, count_t max_len)
  433. {
  434.     wchar_t c1 = 0;
  435.     wchar_t c2 = 0;
  436.    
  437.     size_t off1 = 0;
  438.     size_t off2 = 0;
  439.    
  440.     count_t len = 0;
  441.  
  442.     while (true) {
  443.         if (len >= max_len)
  444.             break;
  445.  
  446.         c1 = str_decode(s1, &off1, STR_NO_LIMIT);
  447.         c2 = str_decode(s2, &off2, STR_NO_LIMIT);
  448.  
  449.         if (c1 < c2)
  450.             return -1;
  451.  
  452.         if (c1 > c2)
  453.             return 1;
  454.  
  455.         if (c1 == 0 || c2 == 0)
  456.             break;
  457.  
  458.         ++len; 
  459.     }
  460.  
  461.     return 0;
  462.  
  463. }
  464.  
  465. /** Copy string.
  466.  *
  467.  * Copy source string @a src to destination buffer @a dest.
  468.  * No more than @a size bytes are written. If the size of the output buffer
  469.  * is at least one byte, the output string will always be well-formed, i.e.
  470.  * null-terminated and containing only complete characters.
  471.  *
  472.  * @param dst   Destination buffer.
  473.  * @param count Size of the destination buffer.
  474.  * @param src   Source string.
  475.  */
  476. void str_cpy(char *dest, size_t size, const char *src)
  477. {
  478.     wchar_t ch;
  479.     size_t src_off;
  480.     size_t dest_off;
  481.  
  482.     /* No space for the NULL-terminator in the buffer. */
  483.     if (size == 0)
  484.         return;
  485.    
  486.     src_off = 0;
  487.     dest_off = 0;
  488.  
  489.     while ((ch = str_decode(src, &src_off, STR_NO_LIMIT)) != 0) {
  490.         if (chr_encode(ch, dest, &dest_off, size - 1) != EOK)
  491.             break;
  492.     }
  493.  
  494.     dest[dest_off] = '\0';
  495. }
  496.  
  497. /** Copy size-limited substring.
  498.  *
  499.  * Copy source string @a src to destination buffer @a dest.
  500.  * No more than @a size bytes are written. If the size of the output buffer
  501.  * is at least one byte, the output string will always be well-formed, i.e.
  502.  * null-terminated and containing only complete characters.
  503.  *
  504.  * No more than @a n bytes are read from the input string, so it does not
  505.  * have to be null-terminated.
  506.  *
  507.  * @param dst   Destination buffer.
  508.  * @param count Size of the destination buffer.
  509.  * @param src   Source string.
  510.  */
  511. void str_ncpy(char *dest, size_t size, const char *src, size_t n)
  512. {
  513.     wchar_t ch;
  514.     size_t src_off;
  515.     size_t dest_off;
  516.  
  517.     /* No space for the null terminator in the buffer. */
  518.     if (size == 0)
  519.         return;
  520.    
  521.     src_off = 0;
  522.     dest_off = 0;
  523.  
  524.     while ((ch = str_decode(src, &src_off, n)) != 0) {
  525.         if (chr_encode(ch, dest, &dest_off, size - 1) != EOK)
  526.             break;
  527.     }
  528.  
  529.     dest[dest_off] = '\0';
  530. }
  531.  
  532. /** Copy NULL-terminated wide string to string
  533.  *
  534.  * Copy source wide string @a src to destination buffer @a dst.
  535.  * No more than @a size bytes are written. NULL-terminator is always
  536.  * written after the last succesfully copied character (i.e. if the
  537.  * destination buffer is has at least 1 byte, it will be always
  538.  * NULL-terminated).
  539.  *
  540.  * @param src   Source wide string.
  541.  * @param dst   Destination buffer.
  542.  * @param count Size of the destination buffer.
  543.  *
  544.  */
  545. void wstr_nstr(char *dst, const wchar_t *src, size_t size)
  546. {
  547.     /* No space for the NULL-terminator in the buffer */
  548.     if (size == 0)
  549.         return;
  550.    
  551.     wchar_t ch;
  552.     count_t src_idx = 0;
  553.     size_t dst_off = 0;
  554.    
  555.     while ((ch = src[src_idx++]) != 0) {
  556.         if (chr_encode(ch, dst, &dst_off, size) != EOK)
  557.             break;
  558.     }
  559.    
  560.     if (dst_off >= size)
  561.         dst[size - 1] = 0;
  562.     else
  563.         dst[dst_off] = 0;
  564. }
  565.  
  566. /** Find first occurence of character in string.
  567.  *
  568.  * @param str String to search.
  569.  * @param ch  Character to look for.
  570.  *
  571.  * @return Pointer to character in @a str or NULL if not found.
  572.  */
  573. const char *str_chr(const char *str, wchar_t ch)
  574. {
  575.     wchar_t acc;
  576.     size_t off = 0;
  577.    
  578.     while ((acc = str_decode(str, &off, STR_NO_LIMIT)) != 0) {
  579.         if (acc == ch)
  580.             return (str + off);
  581.     }
  582.    
  583.     return NULL;
  584. }
  585.  
  586. /** Find last occurence of character in string.
  587.  *
  588.  * @param str String to search.
  589.  * @param ch  Character to look for.
  590.  *
  591.  * @return Pointer to character in @a str or NULL if not found.
  592.  */
  593. const char *str_rchr(const char *str, wchar_t ch)
  594. {
  595.     wchar_t acc;
  596.     size_t off = 0;
  597.     char *res;
  598.  
  599.     res = NULL;
  600.     while ((acc = str_decode(str, &off, STR_NO_LIMIT)) != 0) {
  601.         if (acc == ch)
  602.             res = (str + off);
  603.     }
  604.  
  605.     return res;
  606. }
  607.  
  608. /** Insert a wide character into a wide string.
  609.  *
  610.  * Insert a wide character into a wide string at position
  611.  * @a pos. The characters after the position are shifted.
  612.  *
  613.  * @param str     String to insert to.
  614.  * @param ch      Character to insert to.
  615.  * @param pos     Character index where to insert.
  616.  @ @param max_pos Characters in the buffer.
  617.  *
  618.  * @return True if the insertion was sucessful, false if the position
  619.  *         is out of bounds.
  620.  *
  621.  */
  622. bool wstr_linsert(wchar_t *str, wchar_t ch, count_t pos, count_t max_pos)
  623. {
  624.     count_t len = wstr_length(str);
  625.    
  626.     if ((pos > len) || (pos + 1 > max_pos))
  627.         return false;
  628.    
  629.     count_t i;
  630.     for (i = len; i + 1 > pos; i--)
  631.         str[i + 1] = str[i];
  632.    
  633.     str[pos] = ch;
  634.    
  635.     return true;
  636. }
  637.  
  638. /** Remove a wide character from a wide string.
  639.  *
  640.  * Remove a wide character from a wide string at position
  641.  * @a pos. The characters after the position are shifted.
  642.  *
  643.  * @param str String to remove from.
  644.  * @param pos Character index to remove.
  645.  *
  646.  * @return True if the removal was sucessful, false if the position
  647.  *         is out of bounds.
  648.  *
  649.  */
  650. bool wstr_remove(wchar_t *str, count_t pos)
  651. {
  652.     count_t len = wstr_length(str);
  653.    
  654.     if (pos >= len)
  655.         return false;
  656.    
  657.     count_t i;
  658.     for (i = pos + 1; i <= len; i++)
  659.         str[i - 1] = str[i];
  660.    
  661.     return true;
  662. }
  663.  
  664. int strncmp(const char *a, const char *b, size_t n)
  665. {
  666.     size_t c = 0;
  667.  
  668.     while (c < n && a[c] && b[c] && (!(a[c] - b[c])))
  669.         c++;
  670.    
  671.     return ( c < n ? a[c] - b[c] : 0);
  672.    
  673. }
  674.  
  675. int stricmp(const char *a, const char *b)
  676. {
  677.     int c = 0;
  678.    
  679.     while (a[c] && b[c] && (!(tolower(a[c]) - tolower(b[c]))))
  680.         c++;
  681.    
  682.     return (tolower(a[c]) - tolower(b[c]));
  683. }
  684.  
  685. /** Convert string to a number.
  686.  * Core of strtol and strtoul functions.
  687.  *
  688.  * @param nptr      Pointer to string.
  689.  * @param endptr    If not NULL, function stores here pointer to the first
  690.  *          invalid character.
  691.  * @param base      Zero or number between 2 and 36 inclusive.
  692.  * @param sgn       It's set to 1 if minus found.
  693.  * @return      Result of conversion.
  694.  */
  695. static unsigned long
  696. _strtoul(const char *nptr, char **endptr, int base, char *sgn)
  697. {
  698.     unsigned char c;
  699.     unsigned long result = 0;
  700.     unsigned long a, b;
  701.     const char *str = nptr;
  702.     const char *tmpptr;
  703.    
  704.     while (isspace(*str))
  705.         str++;
  706.    
  707.     if (*str == '-') {
  708.         *sgn = 1;
  709.         ++str;
  710.     } else if (*str == '+')
  711.         ++str;
  712.    
  713.     if (base) {
  714.         if ((base == 1) || (base > 36)) {
  715.             /* FIXME: set errno to EINVAL */
  716.             return 0;
  717.         }
  718.         if ((base == 16) && (*str == '0') && ((str[1] == 'x') ||
  719.             (str[1] == 'X'))) {
  720.             str += 2;
  721.         }
  722.     } else {
  723.         base = 10;
  724.        
  725.         if (*str == '0') {
  726.             base = 8;
  727.             if ((str[1] == 'X') || (str[1] == 'x'))  {
  728.                 base = 16;
  729.                 str += 2;
  730.             }
  731.         }
  732.     }
  733.    
  734.     tmpptr = str;
  735.  
  736.     while (*str) {
  737.         c = *str;
  738.         c = (c >= 'a' ? c - 'a' + 10 : (c >= 'A' ? c - 'A' + 10 :
  739.             (c <= '9' ? c - '0' : 0xff)));
  740.         if (c > base) {
  741.             break;
  742.         }
  743.        
  744.         a = (result & 0xff) * base + c;
  745.         b = (result >> 8) * base + (a >> 8);
  746.        
  747.         if (b > (ULONG_MAX >> 8)) {
  748.             /* overflow */
  749.             /* FIXME: errno = ERANGE*/
  750.             return ULONG_MAX;
  751.         }
  752.    
  753.         result = (b << 8) + (a & 0xff);
  754.         ++str;
  755.     }
  756.    
  757.     if (str == tmpptr) {
  758.         /*
  759.          * No number was found => first invalid character is the first
  760.          * character of the string.
  761.          */
  762.         /* FIXME: set errno to EINVAL */
  763.         str = nptr;
  764.         result = 0;
  765.     }
  766.    
  767.     if (endptr)
  768.         *endptr = (char *) str;
  769.  
  770.     if (nptr == str) {
  771.         /*FIXME: errno = EINVAL*/
  772.         return 0;
  773.     }
  774.  
  775.     return result;
  776. }
  777.  
  778. /** Convert initial part of string to long int according to given base.
  779.  * The number may begin with an arbitrary number of whitespaces followed by
  780.  * optional sign (`+' or `-'). If the base is 0 or 16, the prefix `0x' may be
  781.  * inserted and the number will be taken as hexadecimal one. If the base is 0
  782.  * and the number begin with a zero, number will be taken as octal one (as with
  783.  * base 8). Otherwise the base 0 is taken as decimal.
  784.  *
  785.  * @param nptr      Pointer to string.
  786.  * @param endptr    If not NULL, function stores here pointer to the first
  787.  *          invalid character.
  788.  * @param base      Zero or number between 2 and 36 inclusive.
  789.  * @return      Result of conversion.
  790.  */
  791. long int strtol(const char *nptr, char **endptr, int base)
  792. {
  793.     char sgn = 0;
  794.     unsigned long number = 0;
  795.    
  796.     number = _strtoul(nptr, endptr, base, &sgn);
  797.  
  798.     if (number > LONG_MAX) {
  799.         if ((sgn) && (number == (unsigned long) (LONG_MAX) + 1)) {
  800.             /* FIXME: set 0 to errno */
  801.             return number;     
  802.         }
  803.         /* FIXME: set ERANGE to errno */
  804.         return (sgn ? LONG_MIN : LONG_MAX);
  805.     }
  806.    
  807.     return (sgn ? -number : number);
  808. }
  809.  
  810.  
  811. /** Convert initial part of string to unsigned long according to given base.
  812.  * The number may begin with an arbitrary number of whitespaces followed by
  813.  * optional sign (`+' or `-'). If the base is 0 or 16, the prefix `0x' may be
  814.  * inserted and the number will be taken as hexadecimal one. If the base is 0
  815.  * and the number begin with a zero, number will be taken as octal one (as with
  816.  * base 8). Otherwise the base 0 is taken as decimal.
  817.  *
  818.  * @param nptr      Pointer to string.
  819.  * @param endptr    If not NULL, function stores here pointer to the first
  820.  *          invalid character
  821.  * @param base      Zero or number between 2 and 36 inclusive.
  822.  * @return      Result of conversion.
  823.  */
  824. unsigned long strtoul(const char *nptr, char **endptr, int base)
  825. {
  826.     char sgn = 0;
  827.     unsigned long number = 0;
  828.    
  829.     number = _strtoul(nptr, endptr, base, &sgn);
  830.  
  831.     return (sgn ? -number : number);
  832. }
  833.  
  834. char *strcat(char *dest, const char *src)
  835. {
  836.     char *orig = dest;
  837.     while (*dest++)
  838.         ;
  839.     --dest;
  840.     while ((*dest++ = *src++))
  841.         ;
  842.     return orig;
  843. }
  844.  
  845. char *str_dup(const char *src)
  846. {
  847.     size_t size = str_size(src);
  848.     void *dest = malloc(size + 1);
  849.  
  850.     if (dest == NULL)
  851.         return (char *) NULL;
  852.  
  853.     return (char *) memcpy(dest, src, size + 1);
  854. }
  855.  
  856. char *strtok(char *s, const char *delim)
  857. {
  858.     static char *next;
  859.  
  860.     return strtok_r(s, delim, &next);
  861. }
  862.  
  863. char *strtok_r(char *s, const char *delim, char **next)
  864. {
  865.     char *start, *end;
  866.  
  867.     if (s == NULL)
  868.         s = *next;
  869.  
  870.     /* Skip over leading delimiters. */
  871.     while (*s && (str_chr(delim, *s) != NULL)) ++s;
  872.     start = s;
  873.  
  874.     /* Skip over token characters. */
  875.     while (*s && (str_chr(delim, *s) == NULL)) ++s;
  876.     end = s;
  877.     *next = (*s ? s + 1 : s);
  878.  
  879.     if (start == end) {
  880.         return NULL;    /* No more tokens. */
  881.     }
  882.  
  883.     /* Overwrite delimiter with NULL terminator. */
  884.     *end = '\0';
  885.     return start;
  886. }
  887.  
  888. /** @}
  889.  */
  890.