From 8310940d6803c4298170b2fabd763dc70236e7b0 Mon Sep 17 00:00:00 2001
From: Aki <please@ignore.pl>
Date: Fri, 8 Jul 2022 20:42:16 +0200
Subject: General clean-up, simple docs, code structure, constants

---
 pkgrel.c | 37 ++++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/pkgrel.c b/pkgrel.c
index 22adc8e..78305ca 100644
--- a/pkgrel.c
+++ b/pkgrel.c
@@ -15,13 +15,21 @@ enum match_result
 };
 
 
+static inline size_t minimum(size_t lhs, size_t rhs);
+static char* relative_path_in_current_dir(git_repository* repo, const char* filename);
+static int try_git(int err, const char* msg);
+static int match_line(const git_diff_delta* delta, const git_diff_hunk* hunk, const git_diff_line* line, void* payload);
+
+
+/// Returns the smaller value from *lhs* and *rhs*.
 size_t
-min(const size_t lhs, const size_t rhs)
+minimum(const size_t lhs, const size_t rhs)
 {
 	return lhs > rhs ? rhs : lhs;
 }
 
 
+/// Finds the relative path of *filename* from the workdir of *repo*.
 char*
 relative_path_in_current_dir(git_repository* repo, const char* filename)
 {
@@ -43,7 +51,7 @@ relative_path_in_current_dir(git_repository* repo, const char* filename)
 		}
 	}
 	const char* workdir = git_repository_workdir(repo);
-	const size_t prefix = min(strlen(cwd), strlen(workdir));
+	const size_t prefix = minimum(strlen(cwd), strlen(workdir));
 	if (0 != strncmp(cwd, workdir, prefix)) {
 		free(cwd);
 		return NULL;
@@ -62,13 +70,15 @@ relative_path_in_current_dir(git_repository* repo, const char* filename)
 }
 
 
+/// If *err* is considered erroneous in context of libgit2 return code, print a message describing it, and prefix it
+/// with *msg* if it is not NULL.
 int
-try_git(const int err, const char* optional_prefix)
+try_git(const int err, const char* msg)
 {
 	if (0 > err) {
 		const git_error* e = git_error_last();
-		if (NULL != optional_prefix)
-			dprintf(2, "%s: ", optional_prefix);
+		if (NULL != msg)
+			dprintf(2, "%s: ", msg);
 		dprintf(2, "%s\n", e->message);
 		exit(1);
 	}
@@ -76,16 +86,19 @@ try_git(const int err, const char* optional_prefix)
 }
 
 
+/// Callback for git_diff_foreach. Check each line reported by the diff looking for "pkgver" occurrance. If found, set
+/// *payload* to MATCH_RESULT_FOUND, otherwise set it to MATCH_RESULT_NOTFOUND, but only if it is not set to FOUND
+/// already.
 int
-line_line(const git_diff_delta* delta, const git_diff_hunk* hunk, const git_diff_line* line, void* payload)
+match_line(const git_diff_delta* delta, const git_diff_hunk* hunk, const git_diff_line* line, void* payload)
 {
-	const char* const pkgver = "pkgver";
-	const size_t len = strlen(pkgver);
+	static const char* const PKGVER = "pkgver";
+	static const size_t PKGVER_LEN = 6;
 	enum match_result* matched = (enum match_result*) payload;
 	switch (line->origin) {
 	case GIT_DIFF_LINE_ADDITION:
 	case GIT_DIFF_LINE_DELETION:
-		if (len <= line->content_len && 0 == strncmp(line->content, pkgver, len))
+		if (PKGVER_LEN <= line->content_len && 0 == strncmp(line->content, PKGVER, PKGVER_LEN))
 			*matched = MATCH_RESULT_FOUND;
 		break;
 	default:
@@ -133,7 +146,7 @@ main(int argc, char* argv[])
 		else
 			try_git(git_diff_tree_to_tree(&diff, repo, later, earlier, &diffopts), "diff");
 		enum match_result matched = MATCH_RESULT_INITIAL;
-		try_git(git_diff_foreach(diff, NULL, NULL, NULL, &line_line, &matched), "searching lines");
+		try_git(git_diff_foreach(diff, NULL, NULL, NULL, &match_line, &matched), "searching lines");
 		git_diff_free(diff);
 		git_commit_free(commit);
 		if (MATCH_RESULT_INITIAL != matched)
@@ -143,8 +156,10 @@ main(int argc, char* argv[])
 		if (MATCH_RESULT_NOTFOUND == matched)
 			rel++;
 	}
-	if (0 == occurred)
+	if (0 == occurred) {
 		dprintf(2, "PKGBUILD not found\n");
+		exit(1);
+	}
 	else
 		printf("%d\n", rel);
 }
-- 
cgit v1.1