build: allow to build self-contained executable

1 files changed, 151 insertions, 0 deletions

diff --git a/vis-single.c b/vis-single.c
new file mode 100644
index 0000000..b6296c0
--- /dev/null
+++ b/vis-single.c
@@ -0,0 +1,151 @@
+#define _GNU_SOURCE
+
+#include <ftw.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <archive.h>
+#include <archive_entry.h>
+#include <sys/acl.h>
+
+#include "vis-single-payload.inc"
+
+int copy_data(struct archive *ar, struct archive *aw) {
+	int r;
+	const void *buff;
+	size_t size;
+	int64_t offset;
+
+	for (;;) {
+		if ((r = archive_read_data_block(ar, &buff, &size, &offset)) == ARCHIVE_EOF)
+			return ARCHIVE_OK;
+
+		if (r != ARCHIVE_OK) {
+			fprintf(stderr, "archive_read_data_block() failed: %s\n", archive_error_string(ar));
+			return r;
+		}
+
+		if ((r = archive_write_data_block(aw, buff, size, offset)) != ARCHIVE_OK) {
+			fprintf(stderr, "archive_write_data_block() failed: %s\n", archive_error_string(aw));
+			return r;
+		}
+	}
+
+	return ARCHIVE_OK;
+}
+
+int extract(const char *path) {
+	struct archive *a;
+	struct archive_entry *entry;
+	struct archive *ext;
+	char * abs_path = NULL;
+	const char * term;
+	char * termenv;
+	int r = ARCHIVE_FAILED;
+
+	if ((a = archive_read_new()) == NULL)
+		return ARCHIVE_FAILED;
+
+	if ((r = archive_read_support_filter_xz(a)) != ARCHIVE_OK)
+		goto out10;
+
+	if ((r = archive_read_support_format_tar(a)) != ARCHIVE_OK)
+		goto out10;
+
+	if ((ext = archive_write_disk_new()) == NULL) {
+		r = ARCHIVE_FAILED;
+		goto out10;
+	}
+
+	if ((r = archive_read_open_memory(a, vis_single_payload, sizeof(vis_single_payload))) != ARCHIVE_OK) {
+		fprintf(stderr, "archive_read_open_memory() failed: %s\n", archive_error_string(a));
+		goto out20;
+	}
+
+	while (archive_read_next_header(a, &entry) == ARCHIVE_OK) {
+		if (asprintf(&abs_path, "%s/%s", path, archive_entry_pathname(entry)) == -1)
+			goto out20;
+
+		archive_entry_set_pathname(entry, abs_path);
+		free(abs_path);
+
+		if ((r = archive_write_header(ext, entry)) != ARCHIVE_OK) {
+			fprintf(stderr, "archive_write_header() failed: %s\n", archive_error_string(ext));
+			goto out20;
+		}
+
+		if ((r = copy_data(a, ext)) != ARCHIVE_OK)
+			goto out20;
+
+		if ((r = archive_write_finish_entry(ext)) != ARCHIVE_OK) {
+			fprintf(stderr, "archive_write_finish_entry() failed: %s\n", archive_error_string(ext));
+			goto out20;
+		 }
+	}
+
+out20:
+	archive_write_close(ext);
+	archive_write_free(ext);
+
+out10:
+	archive_read_close(a);
+	archive_read_free(a);
+
+	return ARCHIVE_OK;
+}
+
+int unlink_cb(const char *fpath, const struct stat *sb, int typeflag, struct FTW *ftwbuf) {
+	return remove(fpath);
+}
+
+int main(int argc, char **argv) {
+	char tmp_dirname_template[] = "/tmp/.vis-single-XXXXXX";
+	const char *tmp_dirname;
+	char *abs_path = NULL;
+	const char *term;
+	char *termenv = NULL;
+	int child_pid, statval, rc = EXIT_FAILURE;
+
+	if ((tmp_dirname = mkdtemp(tmp_dirname_template)) == NULL) {
+		perror ("mkdtemp: Could not create tmp directory");
+		goto out10;
+	}
+
+	if (extract(tmp_dirname) != ARCHIVE_OK)
+		goto out20;
+
+	if (asprintf(&abs_path, "%s/vis", tmp_dirname) == -1)
+		goto out20;
+
+	child_pid = fork();
+	if (child_pid == -1) {
+		fprintf(stderr, "could not fork!\n");
+		goto out30;
+	} else if (child_pid == 0) {
+		if ((term = getenv("TERM")) == NULL) {
+			puts("TERM is not defined!");
+			goto out30;
+		}
+
+		if (asprintf(&termenv, "TERM=%s", term) == -1)
+			goto out30;
+
+		char *env[] = { termenv,  NULL };
+		execve(abs_path, argv, env);
+	}
+
+	waitpid(child_pid, &statval, WUNTRACED|WCONTINUED);
+	rc = WEXITSTATUS(statval);
+
+out30:
+	free(abs_path);
+	free(termenv);
+
+out20:
+	nftw(tmp_dirname, unlink_cb, 64, FTW_DEPTH|FTW_PHYS);
+
+out10:
+	return rc;
+}