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Diffstat (limited to 'lib/util.c')
| -rw-r--r-- | lib/util.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/lib/util.c b/lib/util.c new file mode 100644 index 0000000..8c9bc0f --- /dev/null +++ b/lib/util.c @@ -0,0 +1,226 @@ +/** + * @file util.c + */ + +#include "internal.h" +#define _XOPEN_SOURCE 700 +#include <wchar.h> +#include <stdlib.h> +#include <string.h> +#include <ctype.h> +#include <assert.h> + +/** + * Portable strdup. + * + * @param string C "string" to copy. + * @return Copy of the given C "string". + */ +char* _bmStrdup(const char *string) +{ + size_t len = strlen(string); + if (len == 0) + return NULL; + + void *copy = calloc(1, len + 1); + if (copy == NULL) + return NULL; + + return (char *)memcpy(copy, string, len); +} + +/** + * Shrink bmItem** list pointer. + * + * Useful helper function for filter functions. + * + * @param list Pointer to pointer to list of bmItem pointers. + * @param osize Current size of the list. + * @param nsize New size the list will be shrinked to. + * @return Pointer to list of bmItem pointers. + */ +bmItem** _bmShrinkItemList(bmItem ***list, size_t osize, size_t nsize) +{ + if (nsize >= osize) + return *list; + + void *tmp = malloc(sizeof(bmItem*) * nsize); + if (!tmp) + return *list; + + memcpy(tmp, *list, sizeof(bmItem*) * nsize); + free(*list); + *list = tmp; + return *list; +} + +/** + * Determite columns needed to display UTF8 string. + * + * @param string C "string" to determite. + * @return Number of columns, or -1 on failure. + */ +int _bmUtf8StringScreenWidth(const char *string) +{ + if (!string) + return 0; + + int num_char = mbstowcs(NULL, string, 0) + 1; + wchar_t *wstring = malloc((num_char + 1) * sizeof (wstring[0])); + + if (mbstowcs(wstring, string, num_char) == (size_t)(-1)) { + free(wstring); + return strlen(string); + } + + int length = wcswidth(wstring, num_char); + free(wstring); + return length; +} + +/** + * Figure out how many bytes to shift to next UTF8 rune. + * + * @param string C "string" which contains the runes. + * @param start Offset where to figure out next rune. (cursor) + * @return Number of bytes to next UTF8 rune. + */ +size_t _bmUtf8RuneNext(const char *string, size_t start) +{ + assert(string != NULL); + + size_t len = strlen(string), i = start; + if (len == 0 || len <= i || !*string) + return 0; + + while (++i < len && (string[i] & 0xc0) == 0x80); + return i - start; +} + +/** + * Figure out how many bytes to shift to previous UTF8 rune. + * + * @param string C "string" which contains the runes. + * @param start Offset where to figure out previous rune. (cursor) + * @return Number of bytes to previous UTF8 rune. + */ +size_t _bmUtf8RunePrev(const char *string, size_t start) +{ + assert(string != NULL); + + size_t len = strlen(string), i = start; + if (i == 0 || len < start || !*string) + return 0; + + while (--i > 0 && (string[i] & 0xc0) == 0x80); + return start - i; +} + +/** + * Figure out how many columns are needed to display UTF8 rune. + * + * @param rune Buffer which contains the rune. + * @param u8len Byte length of the rune. + * @return Number of columns, or -1 on failure. + */ +size_t _bmUtf8RuneWidth(const char *rune, unsigned int u8len) +{ + assert(rune != NULL); + char mb[5] = { 0, 0, 0, 0, 0 }; + memcpy(mb, rune, (u8len > 4 ? 4 : u8len)); + return _bmUtf8StringScreenWidth(mb); +} + +/** + * Remove previous UTF8 rune from buffer. + * + * @param string Null terminated C "string". + * @param start Start offset where to delete from. (cursor) + * @param runeWidth Reference to size_t, return number of columns for removed rune, or -1 on failure. + * @return Number of bytes removed from buffer. + */ +size_t _bmUtf8RuneRemove(char *string, size_t start, size_t *runeWidth) +{ + assert(string != NULL); + + if (runeWidth) + *runeWidth = 0; + + size_t len = strlen(string), oldStart = start; + if (len == 0 || len < start || !*string) + return 0; + + start -= _bmUtf8RunePrev(string, start); + + if (runeWidth) + *runeWidth = _bmUtf8RuneWidth(string + start, oldStart - start); + + memmove(string + start, string + oldStart, len - oldStart); + string[len - (oldStart - start)] = 0; + return (oldStart - start); +} + +/** + * Insert UTF8 rune to buffer. + * + * @param string Null terminated C "string". + * @param bufSize Size of the buffer. + * @param start Start offset where to insert to. (cursor) + * @param rune Buffer to insert to string. + * @param u8len Byte length of the rune. + * @param runeWidth Reference to size_t, return number of columns for inserted rune, or -1 on failure. + * @return Number of bytes inserted to buffer. + */ +size_t _bmUtf8RuneInsert(char *string, size_t bufSize, size_t start, const char *rune, unsigned int u8len, size_t *runeWidth) +{ + assert(string != NULL); + + if (runeWidth) + *runeWidth = 0; + + size_t len = strlen(string); + if (len + u8len >= bufSize) + return 0; + + if (u8len == 1 && iscntrl(*rune)) + return 0; + + char *str = string + start; + memmove(str + u8len, str, len - start); + memcpy(str, rune, u8len); + + if (runeWidth) + *runeWidth = _bmUtf8RuneWidth(rune, u8len); + return u8len; +} + +/** + * Insert unicode character to UTF8 buffer. + * + * @param string Null terminated C "string". + * @param bufSize Size of the buffer. + * @param start Start offset where to insert to. (cursor) + * @param unicode Unicode character to insert. + * @param runeWidth Reference to size_t, return number of columns for inserted rune, or -1 on failure. + * @return Number of bytes inserted to buffer. + */ +size_t _bmUnicodeInsert(char *string, size_t bufSize, size_t start, unsigned int unicode, size_t *runeWidth) +{ + assert(string != NULL); + + char u8len = ((unicode < 0x80) ? 1 : ((unicode < 0x800) ? 2 : ((unicode < 0x10000) ? 3 : 4))); + char mb[5] = { 0, 0, 0, 0 }; + + if (u8len == 1) { + mb[0] = unicode; + } else { + size_t i, j; + for (i = j = u8len; j > 1; --j) mb[j - 1] = 0x80 | (0x3F & (unicode >> ((i - j) * 6))); + mb[0] = (~0) << (8 - i); + mb[0] |= (unicode >> (i * 6 - 6)); + } + + return _bmUtf8RuneInsert(string, bufSize, start, mb, u8len, runeWidth); +} + +/* vim: set ts=8 sw=4 tw=0 :*/ |