/*++ /* NAME /* strcasecmp_utf8 3 /* SUMMARY /* caseless string comparison /* SYNOPSIS /* #include <stringops.h> /* /* int strcasecmp_utf8( /* const char *s1, /* const char *s2) /* /* int strncasecmp_utf8( /* const char *s1, /* const char *s2, /* ssize_t len) /* AUXILIARY FUNCTIONS /* int strcasecmp_utf8x( /* int flags, /* const char *s1, /* const char *s2) /* /* int strncasecmp_utf8x( /* int flags, /* const char *s1, /* const char *s2, /* ssize_t len) /* DESCRIPTION /* strcasecmp_utf8() implements caseless string comparison for /* UTF-8 text, with an API similar to strcasecmp(). Only ASCII /* characters are casefolded when the code is compiled without /* EAI support or when util_utf8_enable is zero. /* /* strncasecmp_utf8() implements caseless string comparison /* for UTF-8 text, with an API similar to strncasecmp(). Only /* ASCII characters are casefolded when the code is compiled /* without EAI support or when util_utf8_enable is zero. /* /* strcasecmp_utf8x() and strncasecmp_utf8x() implement a more /* complex API that provides the above functionality and more. /* /* Arguments: /* .IP "s1, s2" /* Null-terminated strings to be compared. /* .IP len /* String length before casefolding. /* .IP flags /* Zero or CASEF_FLAG_UTF8. The latter flag enables UTF-8 case /* folding instead of folding only ASCII characters. This flag /* is ignored when compiled without EAI support. /* SEE ALSO /* casefold(), casefold text for caseless comparison. /* LICENSE /* .ad /* .fi /* The Secure Mailer license must be distributed with this software. /* AUTHOR(S) /* Wietse Venema /* IBM T.J. Watson Research /* P.O. Box 704 /* Yorktown Heights, NY 10598, USA /* /* Wietse Venema /* Google, Inc. /* 111 8th Avenue /* New York, NY 10011, USA /*--*/ /* * System library. */ #include <sys_defs.h> #include <string.h> #ifdef STRCASECMP_IN_STRINGS_H #include <strings.h> #endif /* * Utility library. */ #include <stringops.h> #define STR(x) vstring_str(x) static VSTRING *f1; /* casefold result for s1 */ static VSTRING *f2; /* casefold result for s2 */ /* strcasecmp_utf8_init - initialize */ static void strcasecmp_utf8_init(void) { f1 = vstring_alloc(100); f2 = vstring_alloc(100); } /* strcasecmp_utf8x - caseless string comparison */ int strcasecmp_utf8x(int flags, const char *s1, const char *s2) { /* * Short-circuit optimization for ASCII-only text. This may be slower * than using a cache for all results. We must not expose strcasecmp(3) * to non-ASCII text. */ if (allascii(s1) && allascii(s2)) return (strcasecmp(s1, s2)); if (f1 == 0) strcasecmp_utf8_init(); /* * Cross our fingers and hope that strcmp() remains agnostic of * charactersets and locales. */ flags &= CASEF_FLAG_UTF8; casefoldx(flags, f1, s1, -1); casefoldx(flags, f2, s2, -1); return (strcmp(STR(f1), STR(f2))); } /* strncasecmp_utf8x - caseless string comparison */ int strncasecmp_utf8x(int flags, const char *s1, const char *s2, ssize_t len) { /* * Consider using a cache for all results. */ if (f1 == 0) strcasecmp_utf8_init(); /* * Short-circuit optimization for ASCII-only text. This may be slower * than using a cache for all results. See comments above for limitations * of strcasecmp(). */ if (allascii_len(s1, len) && allascii_len(s2, len)) return (strncasecmp(s1, s2, len)); /* * Caution: casefolding may change the number of bytes. See comments * above for concerns about strcmp(). */ flags &= CASEF_FLAG_UTF8; casefoldx(flags, f1, s1, len); casefoldx(flags, f2, s2, len); return (strcmp(STR(f1), STR(f2))); } #ifdef TEST #include <stdio.h> #include <stdlib.h> #include <vstream.h> #include <vstring_vstream.h> #include <msg_vstream.h> #include <argv.h> int main(int argc, char **argv) { VSTRING *buffer = vstring_alloc(1); ARGV *cmd; char **args; int len; int flags; int res; msg_vstream_init(argv[0], VSTREAM_ERR); flags = CASEF_FLAG_UTF8; util_utf8_enable = 1; while (vstring_fgets_nonl(buffer, VSTREAM_IN)) { vstream_printf("> %s\n", STR(buffer)); cmd = argv_split(STR(buffer), CHARS_SPACE); if (cmd->argc == 0 || cmd->argv[0][0] == '#') continue; args = cmd->argv; /* * Compare two strings. */ if (strcmp(args[0], "compare") == 0 && cmd->argc == 3) { res = strcasecmp_utf8x(flags, args[1], args[2]); vstream_printf("\"%s\" %s \"%s\"\n", args[1], res < 0 ? "<" : res == 0 ? "==" : ">", args[2]); } /* * Compare two substrings. */ else if (strcmp(args[0], "compare-len") == 0 && cmd->argc == 4 && sscanf(args[3], "%d", &len) == 1 && len >= 0) { res = strncasecmp_utf8x(flags, args[1], args[2], len); vstream_printf("\"%.*s\" %s \"%.*s\"\n", len, args[1], res < 0 ? "<" : res == 0 ? "==" : ">", len, args[2]); } /* * Usage. */ else { vstream_printf("Usage: %s compare <s1> <s2> | compare-len <s1> <s2> <len>\n", argv[0]); } vstream_fflush(VSTREAM_OUT); argv_free(cmd); } exit(0); } #endif /* TEST */