examples: ls-files: show current files in index

examples/ls-files.c

-#include <common.h>
+/*
+ * libgit2 "ls-files" example - shows how to view all files currently in the index
+ *
+ * Written by the libgit2 contributors
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide. This software is distributed without any warranty.
+ *
+ * You should have received a copy of the CC0 Public Domain Dedication along
+ * with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
+ */
 
-typedef struct ls_files_state {
+#include "common.h"
+
+/**
+ * This example demonstrates the libgit2 index APIs to roughly
+ * simulate the output of `git ls-files`.
+ * `git ls-files` has many options and this currently does not show them.
+ * 
+ * `git ls-files` base command shows all paths in the index at that time.
+ * This includes staged and committed files, but unstaged files will not display.
+ */
+
+#define MAX_FILES 64
+
+typedef struct ls_options {
+	int error_unmatch;
+	char *files[MAX_FILES];
+	int file_count;
+} ls_options;
+
+void parse_options(ls_options *opts, int argc, char *argv[]);
+
+int main(int argc, char *argv[]) {
+	ls_options opts;
 	git_repository *repo;
 	git_index *index;
-	char **files;
-	size_t num_entries;
-} ls_files;
-
-void create_ls_files(ls_files **ls);
+	const git_index_entry *entry;
+	size_t entry_count;
+	size_t i = 0;
+	int error;
 
-int main(int argc, char[] *argv) {
-	ls_files *ls;
-	git_index_entry *entry;
-	size_t i;
+	parse_options(&opts, argc, argv);
 
+	/* we need to initialize libgit2 */
 	git_libgit2_init();
 
-	ls = git__malloc(sizeof(ls_files));
+	/* we need to open the repo */
+	if ((error = git_repository_open_ext(&repo, ".", 0, NULL)) != 0)
+		goto cleanup;
 
-	// TODO err
-	git_repository_open_ext(&ls->repo, ".", 0, NULL);
+	/* we need to load the repo's index */
+	if ((error = git_repository_index(&index, repo)) != 0)
+		goto cleanup;
 
-	// TODO err
-	git_repository_index__weakptr(&ls->index, ls->repo);
+	if (opts.error_unmatch) {
+		for (i = 0; i < opts.file_count; i++) {
+			const char *path = opts.files[i];
+			printf("Checking first path '%s'\n", path);
+			entry = git_index_get_bypath(index, path, GIT_INDEX_STAGE_NORMAL);
+			if (!entry) {
+				printf("Could not find path '%s'\n", path);
+				return -1;
+			}
+		}
+		goto cleanup;
+	}
 
+	/* we need to know how many entries exist in the index */
+	entry_count = git_index_entrycount(index);
 
-	git_vector_foreach(&ls->index->entries, i, entry) {
+	/* loop through the entries by index and display their pathes */
+	for (i = 0; i < entry_count; i++) {
+		entry = git_index_get_byindex(index, i);
 		printf("%s\n", entry->path);
 	}
 
-	git_repository_free(ls->repo);
-	git__free(ls);
+cleanup:
+	/* free our allocated resources */
+	git_index_free(index);
+	git_repository_free(repo);
+
+	/* we need to shutdown libgit2 */
 	git_libgit2_shutdown();
 
-	return 0;
+	return error;
 }
+
+void parse_options(ls_options *opts, int argc, char *argv[]) {
+	int parsing_files = 0;
+	int file_idx = 0;
+	struct args_info args = ARGS_INFO_INIT;
+	
+	memset(opts, 0, sizeof(ls_options));
+	opts->error_unmatch = 0;
+	opts->file_count = 0;
+
+	if (argc < 2)
+		return;
+
+	for (args.pos = 1; args.pos < argc; ++args.pos) {
+		char *a = argv[args.pos];
+
+		if (a[0] != '-' || !strcmp(a, "--")) {
+			if (parsing_files) {
+				printf("%s\n", a);
+				opts->files[opts->file_count++] = a;
+			} else { 
+				parsing_files = 1;
+			}
+		} else if (!strcmp(a, "--error-unmatch")) {
+			opts->error_unmatch = 1;
+			parsing_files = 1;
+		} else {
+			printf("Bad command\n");
+		}
+	}
+
+	printf("file count: %d\n", opts->file_count);
+	int i;
+	for (i = 0; i < opts->file_count; i++) {
+		printf("Path ids %d: %s\n", i, opts->files[i]);
+	}
+ }