merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 66 insertions, 28 deletions

diff --git a/third_party/git/t/helper/test-regex.c b/third_party/git/t/helper/test-regex.c
index 10284cc56fa9..d6f28ca8d148 100644
--- a/third_party/git/t/helper/test-regex.c
+++ b/third_party/git/t/helper/test-regex.c
@@ -1,5 +1,4 @@
 #include "test-tool.h"
-#include "git-compat-util.h"
 #include "gettext.h"
 
 struct reg_flag {
@@ -8,12 +7,13 @@ struct reg_flag {
 };
 
 static struct reg_flag reg_flags[] = {
-	{ "EXTENDED",	 REG_EXTENDED	},
-	{ "NEWLINE",	 REG_NEWLINE	},
-	{ "ICASE",	 REG_ICASE	},
-	{ "NOTBOL",	 REG_NOTBOL	},
+	{ "EXTENDED",	REG_EXTENDED	},
+	{ "NEWLINE",	REG_NEWLINE	},
+	{ "ICASE",	REG_ICASE	},
+	{ "NOTBOL",	REG_NOTBOL	},
+	{ "NOTEOL",	REG_NOTEOL	},
 #ifdef REG_STARTEND
-	{ "STARTEND",	 REG_STARTEND	},
+	{ "STARTEND",	REG_STARTEND	},
 #endif
 	{ NULL, 0 }
 };
@@ -41,36 +41,74 @@ int cmd__regex(int argc, const char **argv)
 {
 	const char *pat;
 	const char *str;
-	int flags = 0;
+	int ret, silent = 0, flags = 0;
 	regex_t r;
 	regmatch_t m[1];
-
-	if (argc == 2 && !strcmp(argv[1], "--bug"))
-		return test_regex_bug();
-	else if (argc < 3)
-		usage("test-tool regex --bug\n"
-		      "test-tool regex <pattern> <string> [<options>]");
+	char errbuf[64];
 
 	argv++;
-	pat = *argv++;
-	str = *argv++;
-	while (*argv) {
-		struct reg_flag *rf;
-		for (rf = reg_flags; rf->name; rf++)
-			if (!strcmp(*argv, rf->name)) {
-				flags |= rf->flag;
-				break;
-			}
-		if (!rf->name)
-			die("do not recognize %s", *argv);
+	argc--;
+
+	if (!argc)
+		goto usage;
+
+	if (!strcmp(*argv, "--bug")) {
+		if (argc == 1)
+			return test_regex_bug();
+		else
+			goto usage;
+	}
+	if (!strcmp(*argv, "--silent")) {
+		silent = 1;
 		argv++;
+		argc--;
+	}
+	if (!argc)
+		goto usage;
+
+	pat = *argv++;
+	if (argc == 1)
+		str = NULL;
+	else {
+		str = *argv++;
+		while (*argv) {
+			struct reg_flag *rf;
+			for (rf = reg_flags; rf->name; rf++)
+				if (!strcmp(*argv, rf->name)) {
+					flags |= rf->flag;
+					break;
+				}
+			if (!rf->name)
+				die("do not recognize flag %s", *argv);
+			argv++;
+		}
 	}
 	git_setup_gettext();
 
-	if (regcomp(&r, pat, flags))
-		die("failed regcomp() for pattern '%s'", pat);
-	if (regexec(&r, str, 1, m, 0))
-		return 1;
+	ret = regcomp(&r, pat, flags);
+	if (ret) {
+		if (silent)
+			return ret;
+
+		regerror(ret, &r, errbuf, sizeof(errbuf));
+		die("failed regcomp() for pattern '%s' (%s)", pat, errbuf);
+	}
+	if (!str)
+		return 0;
+
+	ret = regexec(&r, str, 1, m, 0);
+	if (ret) {
+		if (silent || ret == REG_NOMATCH)
+			return ret;
+
+		regerror(ret, &r, errbuf, sizeof(errbuf));
+		die("failed regexec() for subject '%s' (%s)", str, errbuf);
+	}
 
 	return 0;
+usage:
+	usage("\ttest-tool regex --bug\n"
+	      "\ttest-tool regex [--silent] <pattern>\n"
+	      "\ttest-tool regex [--silent] <pattern> <string> [<options>]");
+	return -1;
 }