NAMEunac - remove accents from string or character
SYNOPSIS#include <unac.h> const char* unac_version(); int unac_string(const char* charset, const char* in, int in_length, char** out, int* out_length); int unac_string_utf16(const char* in, int in_length, char** out, int* out_length); /* MACRO: side effect on unaccented and length arguments */ unac_char_utf16(unsigned short c, unsigned short* unaccented, int length); const char* unac_version() /* * The level argument can be one of: * UNAC_DEBUG_NONE UNAC_DEBUG_LOW UNAC_DEBUG_HIGH */ void unac_debug(int level) typedef void (*unac_debug_print_t)(const char* message, void* data); void unac_debug_callback(int level, unac_debug_print_t function, void* data)
DESCRIPTIONunac is a C library that removes accents from characters, regardless of the character set (ISO-8859-15, ISO-CELTIC, KOI8-RU...) as long as iconv(3) is able to convert it into UTF-16 (Unicode). The unac_string function is given a charset (ISO-8859-15 for instance) and a string. It converts the string into UTF-16 and calls the unac_string_utf16 function to remove all accents from the UTF-16 version. The unaccented string is then converted into the original charset (ISO-8859-15 for instance) and returned to the caller of unac_string. unac does a little more than removing accents: every character that is made of two character such as ae (ISO-8859-15 octal code 346) will be expanded in two characters a and e. Should a character be made of three characters, it would be decomposed in the same way. The conversion from and to UTF-16 is done with iconv(3). The iconv -l command will list all available charsets. Using UTF-16 as a pivot implies an overhead but ensures that accents can be removed from all character for which there is an equivalent character in Unicode. unac_char_utf16 is a CPP macro that returns a pointer to the unaccented equivalent of a given UTF-16 character. It is the basic building block of unac. unac_string_utf16 repeatidly applies the unac_char_utf16 macro to each character of an UTF-16 string.
FUNCTIONSint unac_string(const char* charset, const char* in, size_t in_length, char** out, size_t* out_length) Returns the unaccented equivalent of the string 'in' of length 'in_length' bytes. The returned string is stored in the pointer pointed by the 'out' argument and the length of the 'out' string, in bytes, is stored in the integer pointed by the 'out_length ' argument. If the '*out' pointer is not null, it must point to an area allocated by malloc(3) and the length of the array must be specified in the '*out_length' argument. Both arguments '*out' and '*out_length' will be replaced with the return values when the function returns on success. The '*out' pointer may point to a memory location that has been reallocated (using realloc(3)) by the unac_string function. There is no guarantee that '*out' is identical to the value given by the caller. The pointer provided as '*out' by the caller may not be useable when the function returns (either error or success). If the '*out' pointer is null, the unac_string function allocates a new memory block using malloc(3). It is the responsibility of the caller to deallocate the area returned in the '*out' pointer. The return value of unac_string is 0 on success and -1 on error, in which case the errno variable is set to the corresponding error code. See the ERROR section below for more information. The iconv(3) manual page may also help. int unac_string_utf16(const char* in, int in_length, char** out, int* out_length) Has the same effect as unac_string("UTF-16", in, in_length, out, out_length). Since the unac_string_utf16 is the backend function of the unac_string function it is more efficient because no charset conversion of the input string (from and to UTF-16) is necessary. unac_char_utf16(const unsigned short c, unsigned short* p, int l) Warning: this is a macro, each argument may be evaluated more than once. Returns the unaccented equivalent of the UTF-16 character 'c' in the pointer 'p'. The length of the unsigned short array pointed by 'p' is returned in the 'l' argument. const char* unac_version() Return the version number of unac. void unac_debug(int level) Set the debug level of the unac library to 'level'. Possible values are: UNAC_DEBUG_NONE for no debug at all, UNAC_DEBUG_LOW for terse human readable information, UNAC_DEBUG_HIGH for very detailed information only usable when translating a few strings. unac_debug_callback with anything but UNAC_DEBUG_NONE is not thread safe. void unac_debug_callback(int level, unac_debug_print_t function, void* data) Set the debug level and define a printing function callback. The 'level' is the same as in unac_debug. The 'function' is in charge of dealing with the debug messages, presumably to print them to the user. The 'data' is an opaque pointer that is passed along to function, should it need to manage a persistent context. The prototype of 'function' accepts two arguments. The first is the debug message (const char*), the second is the opaque pointer given as 'data' argument to unac_debug_callback. If 'function' is NULL, messages are printed on the standard error output using fprintf(stderr...). unac_debug_callback with anything but UNAC_DEBUG_NONE is not thread safe.
ERRORSEINVAL the requested conversion pair is not available. For instance, when specifying the ISO-0000 charset (imaginary), it means it is not possible to convert from ISO-0000 to UTF-16.
EXAMPLESConvert the '
BUGSThe input string must not contain partially formed characters, there is no support for this case. UTF-16 surrogates are not handled. Unicode may contain bugs in the decomposition of characters. When you suspect such a bug on a given string, add a test case with the faulty string in the t_unac.in test script (you will find it in the source distribution) and run make check. It will describe, in a very verbose way, how the string was unaccented. You may then fix the UnicodeData-4.0.0.txt file and run make check again to make sure the problem is solved. Please send such fixes to the author and to the Unicode consortium.
SEE ALSOunaccent(1), iconv(3) //www.unicode.org/ //oss.software.ibm.com/icu/ //www.gnu.org/manual/glibc-2.2.5/libc.html
AUTHORLoic Dachary firstname.lastname@example.org //www.senga.org/unac/ local UNAC(3)