Added support for shell (and csh as well) patterns for required

dependencies, as specified in blueprint "improved-version-matching".

It's possible now to require greater, greater or equal than,
less, less or equal than, and equal pkg versions, as well as using
'{}' and '[^!]' csh patterns in dependencies.

Code lifted from FreeBSD, thanks! :-)

Change XBPS_RELVER to 20091107 to match latest additions.

--HG--
extra : convert_revision : xtraeme%40gmail.com-20091107035620-3051wcwrirqn2g14

lib/pkgmatch.c

@@ -0,0 +1,170 @@
+/*
+ * FreeBSD install - a package for the installation and maintenance
+ * of non-core utilities.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * Maxim Sobolev
+ * 31 July 2001
+ *
+ */
+
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <limits.h>
+#include <fnmatch.h>
+
+#include <xbps_api.h>
+
+static int
+csh_match(const char *pattern, const char *string, int flags)
+{
+	const char *nextchoice = pattern, *current = NULL;
+	int ret = FNM_NOMATCH, prefixlen = -1, curlen = 0, level = 0;
+
+	do {
+		const char *pos = nextchoice;
+		const char *postfix = NULL;
+		bool quoted = false;
+
+		nextchoice = NULL;
+		do {
+			const char *eb;
+			if (!*pos) {
+				postfix = pos;
+			} else if (quoted) {
+				quoted = false;
+			} else {
+				switch (*pos) {
+				case '{':
+					++level;
+					if (level == 1) {
+						current = pos + 1;
+						prefixlen = pos - pattern;
+					}
+					break;
+				case ',':
+					if (level == 1 && !nextchoice) {
+						nextchoice = pos + 1;
+						curlen = pos - current;
+					}
+					break;
+				case '}':
+					if (level == 1) {
+						postfix = pos + 1;
+						if (!nextchoice)
+							curlen = pos - current;
+					}
+					level--;
+					break;
+				case '[':
+					eb = pos+1;
+					if (*eb == '!' || *eb == '^')
+						eb++;
+					if (*eb == ']')
+						eb++;
+					while (*eb && *eb != ']')
+						eb++;
+					if (*eb)
+						pos = eb;
+					break;
+				case '\\':
+					quoted = true;
+					break;
+				default:
+					;
+				}
+			}
+			pos++;
+		} while (!postfix);
+
+		if (current) {
+			char buf[FILENAME_MAX];
+			snprintf(buf, sizeof(buf), "%.*s%.*s%s", prefixlen,
+			    pattern, curlen, current, postfix);
+			ret = csh_match(buf, string, flags);
+			if (ret) {
+				current = nextchoice;
+				level = 1;
+			} else
+				current = NULL;
+		} else
+			ret = fnmatch(pattern, string, flags);
+	} while (current);
+
+	return ret;
+}
+
+int SYMEXPORT
+xbps_pkgdep_match(const char *instpkg, char *pattern)
+{
+	const char *fname = instpkg;
+	char basefname[PATH_MAX], condchar = '\0', *condition;
+	int rv = 0;
+
+	condition = strpbrk(pattern, "><=");
+	if (condition) {
+		const char *ch;
+		if (condition > pattern && condition[-1] == '!')
+			condition--;
+		condchar = *condition;
+		*condition = '\0';
+		ch = strrchr(fname, '-');
+		if (ch && ch - fname < PATH_MAX) {
+			strncpy(basefname, fname, ch - fname);
+			fname = basefname;
+		}
+	}
+
+	rv = (csh_match(pattern, fname, 0) == 0) ? 1 : 0;
+
+	while (condition) {
+		*condition = condchar;
+		if (rv == 1) {
+			char *nextcondition;
+			int match = 0;
+			if (*++condition == '=') {
+				match = 2;
+				condition++;
+			}
+			switch (condchar) {
+			case '<':
+				match |= 1;
+				break;
+			case '>':
+				match |= 4;
+				break;
+			case '=':
+				match |= 2;
+				break;
+			case '!':
+				match = 5;
+				break;
+			}
+			nextcondition = strpbrk(condition, "<>=!");
+			if (nextcondition) {
+				condchar = *nextcondition;
+				*nextcondition = '\0';
+			}
+			if ((match &
+			    (1 << (xbps_cmpver(instpkg, condition) + 1))) == 0)
+				rv = 0;
+			condition = nextcondition;
+		} else {
+			break;
+		}
+	}
+
+	return rv;
+}