wildmatch.c

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/*
**  Do shell-style pattern matching for ?, \, [], and * characters.
**  It is 8bit clean.
**
**  Written by Rich $alz, mirror!rs, Wed Nov 26 19:03:17 EST 1986.
**  Rich $alz is now <rsalz@bbn.com>.
**
**  Modified by Wayne Davison to special-case '/' matching, to make '**'
**  work differently than '*', and to fix the character-class code.
*/

#include "git-compat-util.h"
#include "wildmatch.h"

typedef unsigned char uchar;

/* Internal return values */
#define WM_ABORT_ALL -1
#define WM_ABORT_TO_STARSTAR -2

/* What character marks an inverted character class? */
#define NEGATE_CLASS    '!'
#define NEGATE_CLASS2    '^'

#define CC_EQ(class, len, litmatch) ((len) == sizeof (litmatch)-1 \
                    && *(class) == *(litmatch) \
                    && strncmp((char*)class, litmatch, len) == 0)

#if defined STDC_HEADERS || !defined isascii
# define ISASCII(c) 1
#else
# define ISASCII(c) isascii(c)
#endif

#ifdef isblank
# define ISBLANK(c) (ISASCII(c) && isblank(c))
#else
# define ISBLANK(c) ((c) == ' ' || (c) == '\t')
#endif

#ifdef isgraph
# define ISGRAPH(c) (ISASCII(c) && isgraph(c))
#else
# define ISGRAPH(c) (ISASCII(c) && isprint(c) && !isspace(c))
#endif

#define ISPRINT(c) (ISASCII(c) && isprint(c))
#define ISDIGIT(c) (ISASCII(c) && isdigit(c))
#define ISALNUM(c) (ISASCII(c) && isalnum(c))
#define ISALPHA(c) (ISASCII(c) && isalpha(c))
#define ISCNTRL(c) (ISASCII(c) && iscntrl(c))
#define ISLOWER(c) (ISASCII(c) && islower(c))
#define ISPUNCT(c) (ISASCII(c) && ispunct(c))
#define ISSPACE(c) (ISASCII(c) && isspace(c))
#define ISUPPER(c) (ISASCII(c) && isupper(c))
#define ISXDIGIT(c) (ISASCII(c) && isxdigit(c))

/* Match pattern "p" against "text" */
static int dowild(const uchar *p, const uchar *text, unsigned int flags)
{
    uchar p_ch;
    const uchar *pattern = p;

    for ( ; (p_ch = *p) != '\0'; text++, p++) {
        int matched, match_slash, negated;
        uchar t_ch, prev_ch;
        if ((t_ch = *text) == '\0' && p_ch != '*')
            return WM_ABORT_ALL;
        if ((flags & WM_CASEFOLD) && ISUPPER(t_ch))
            t_ch = tolower(t_ch);
        if ((flags & WM_CASEFOLD) && ISUPPER(p_ch))
            p_ch = tolower(p_ch);
        switch (p_ch) {
        case '\\':
            /* Literal match with following character.  Note that the test
             * in "default" handles the p[1] == '\0' failure case. */
            p_ch = *++p;
            /* FALLTHROUGH */
        default:
            if (t_ch != p_ch)
                return WM_NOMATCH;
            continue;
        case '?':
            /* Match anything but '/'. */
            if ((flags & WM_PATHNAME) && t_ch == '/')
                return WM_NOMATCH;
            continue;
        case '*':
            if (*++p == '*') {
                const uchar *prev_p = p;
                while (*++p == '*') {}
                if (!(flags & WM_PATHNAME))
                    /* without WM_PATHNAME, '*' == '**' */
                    match_slash = 1;
                else if ((prev_p - pattern < 2 || *(prev_p - 2) == '/') &&
                    (*p == '\0' || *p == '/' ||
                     (p[0] == '\\' && p[1] == '/'))) {
                    /*
                     * Assuming we already match 'foo/' and are at
                     * <star star slash>, just assume it matches
                     * nothing and go ahead match the rest of the
                     * pattern with the remaining string. This
                     * helps make foo/<*><*>/bar (<> because
                     * otherwise it breaks C comment syntax) match
                     * both foo/bar and foo/a/bar.
                     */
                    if (p[0] == '/' &&
                        dowild(p + 1, text, flags) == WM_MATCH)
                        return WM_MATCH;
                    match_slash = 1;
                } else /* WM_PATHNAME is set */
                    match_slash = 0;
            } else
                /* without WM_PATHNAME, '*' == '**' */
                match_slash = flags & WM_PATHNAME ? 0 : 1;
            if (*p == '\0') {
                /* Trailing "**" matches everything.  Trailing "*" matches
                 * only if there are no more slash characters. */
                if (!match_slash) {
                    if (strchr((char *)text, '/'))
                        return WM_ABORT_TO_STARSTAR;
                }
                return WM_MATCH;
            } else if (!match_slash && *p == '/') {
                /*
                 * _one_ asterisk followed by a slash
                 * with WM_PATHNAME matches the next
                 * directory
                 */
                const char *slash = strchr((char*)text, '/');
                if (!slash)
                    return WM_ABORT_ALL;
                text = (const uchar*)slash;
                /* the slash is consumed by the top-level for loop */
                break;
            }
            while (1) {
                if (t_ch == '\0')
                    break;
                /*
                 * Try to advance faster when an asterisk is
                 * followed by a literal. We know in this case
                 * that the string before the literal
                 * must belong to "*".
                 * If match_slash is false, do not look past
                 * the first slash as it cannot belong to '*'.
                 */
                if (!is_glob_special(*p)) {
                    p_ch = *p;
                    if ((flags & WM_CASEFOLD) && ISUPPER(p_ch))
                        p_ch = tolower(p_ch);
                    while ((t_ch = *text) != '\0' &&
                           (match_slash || t_ch != '/')) {
                        if ((flags & WM_CASEFOLD) && ISUPPER(t_ch))
                            t_ch = tolower(t_ch);
                        if (t_ch == p_ch)
                            break;
                        text++;
                    }
                    if (t_ch != p_ch) {
                        if (match_slash)
                            return WM_ABORT_ALL;
                        else
                            return WM_ABORT_TO_STARSTAR;
                    }
                }
                if ((matched = dowild(p, text, flags)) != WM_NOMATCH) {
                    if (!match_slash || matched != WM_ABORT_TO_STARSTAR)
                        return matched;
                } else if (!match_slash && t_ch == '/')
                    return WM_ABORT_TO_STARSTAR;
                t_ch = *++text;
            }
            return WM_ABORT_ALL;
        case '[':
            p_ch = *++p;
#ifdef NEGATE_CLASS2
            if (p_ch == NEGATE_CLASS2)
                p_ch = NEGATE_CLASS;
#endif
            /* Assign literal 1/0 because of "matched" comparison. */
            negated = p_ch == NEGATE_CLASS ? 1 : 0;
            if (negated) {
                /* Inverted character class. */
                p_ch = *++p;
            }
            prev_ch = 0;
            matched = 0;
            do {
                if (!p_ch)
                    return WM_ABORT_ALL;
                if (p_ch == '\\') {
                    p_ch = *++p;
                    if (!p_ch)
                        return WM_ABORT_ALL;
                    if (t_ch == p_ch)
                        matched = 1;
                } else if (p_ch == '-' && prev_ch && p[1] && p[1] != ']') {
                    p_ch = *++p;
                    if (p_ch == '\\') {
                        p_ch = *++p;
                        if (!p_ch)
                            return WM_ABORT_ALL;
                    }
                    if (t_ch <= p_ch && t_ch >= prev_ch)
                        matched = 1;
                    else if ((flags & WM_CASEFOLD) && ISLOWER(t_ch)) {
                        uchar t_ch_upper = toupper(t_ch);
                        if (t_ch_upper <= p_ch && t_ch_upper >= prev_ch)
                            matched = 1;
                    }
                    p_ch = 0; /* This makes "prev_ch" get set to 0. */
                } else if (p_ch == '[' && p[1] == ':') {
                    const uchar *s;
                    int i;
                    for (s = p += 2; (p_ch = *p) && p_ch != ']'; p++) {} /*SHARED ITERATOR*/
                    if (!p_ch)
                        return WM_ABORT_ALL;
                    i = p - s - 1;
                    if (i < 0 || p[-1] != ':') {
                        /* Didn't find ":]", so treat like a normal set. */
                        p = s - 2;
                        p_ch = '[';
                        if (t_ch == p_ch)
                            matched = 1;
                        continue;
                    }
                    if (CC_EQ(s,i, "alnum")) {
                        if (ISALNUM(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "alpha")) {
                        if (ISALPHA(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "blank")) {
                        if (ISBLANK(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "cntrl")) {
                        if (ISCNTRL(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "digit")) {
                        if (ISDIGIT(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "graph")) {
                        if (ISGRAPH(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "lower")) {
                        if (ISLOWER(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "print")) {
                        if (ISPRINT(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "punct")) {
                        if (ISPUNCT(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "space")) {
                        if (ISSPACE(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "upper")) {
                        if (ISUPPER(t_ch))
                            matched = 1;
                        else if ((flags & WM_CASEFOLD) && ISLOWER(t_ch))
                            matched = 1;
                    } else if (CC_EQ(s,i, "xdigit")) {
                        if (ISXDIGIT(t_ch))
                            matched = 1;
                    } else /* malformed [:class:] string */
                        return WM_ABORT_ALL;
                    p_ch = 0; /* This makes "prev_ch" get set to 0. */
                } else if (t_ch == p_ch)
                    matched = 1;
            } while (prev_ch = p_ch, (p_ch = *++p) != ']');
            if (matched == negated ||
                ((flags & WM_PATHNAME) && t_ch == '/'))
                return WM_NOMATCH;
            continue;
        }
    }

    return *text ? WM_NOMATCH : WM_MATCH;
}

/* Match the "pattern" against the "text" string. */
int wildmatch(const char *pattern, const char *text, unsigned int flags)
{
    int res = dowild((const uchar*)pattern, (const uchar*)text, flags);
    return res == WM_MATCH ? WM_MATCH : WM_NOMATCH;
}