From: Nathan Wagner <nw@hydaspes.if.org>
Date: Thu, 25 Oct 2018 17:12:08 +0000 (+0000)
Subject: use tempfile when extracting
X-Git-Tag: v0.2.16~57
X-Git-Url: https://pd.if.org/git/?p=zpackage;a=commitdiff_plain;h=a63f09fb0e19460727bc6a31b3a401a53e54e58f

use tempfile when extracting
---

diff --git a/lib/zpm.c b/lib/zpm.c
index 644dc97..f0a0ba2 100644
--- a/lib/zpm.c
+++ b/lib/zpm.c
@@ -449,16 +449,19 @@ int zpm_addvercmp(struct zpm *pkg) {
 
 int zpm_extract(struct zpm *pkg, char *hash, char *path, mode_t mode) {
 	int rc;
-
 	int blobsize;
-	//int64_t size;
 	void *xzdata;
 	int type;
 	int out;
 	sqlite3_stmt *ifile;
+	size_t len;
+	char *tmpfile = 0;
+	sqlite3 *db;
 
-	/* TODO check null */
-	sqlite3 *db = pkg->db;
+	if (!pkg || !pkg->db) {
+		return 0;
+	}
+	db = pkg->db;
 
 	rc = sqlite3_prepare(db, "select size, content from files where hash = ?", -1, &ifile,0);
 	if (rc != SQLITE_OK) {
@@ -507,26 +510,55 @@ int zpm_extract(struct zpm *pkg, char *hash, char *path, mode_t mode) {
 	blobsize = sqlite3_column_bytes(ifile, 1);
 
 	if (strcmp(path, "-")) {
-		out = open(path, O_CREAT|O_WRONLY|O_TRUNC, 0600);
+		len = strlen(path);
+		tmpfile = malloc(len+8+1);
+		if (!tmpfile) {
+			fprintf(stderr, "malloc error\n");
+			return 0;
+		}
+		sprintf(tmpfile, "%sXXXXXX", path);
+
+		out = open(tmpfile, O_CREAT|O_WRONLY|O_TRUNC, 0600);
+		if (out == -1) {
+			fprintf(stderr, "can't open output file %s: %s\n",
+					tmpfile, strerror(errno));
+			sqlite3_finalize(ifile);
+		       	sqlite3_close(db);
+		       	return 0;
+		}
 	} else {
 		out = 1;
 	}
-	if (out == -1) {
-		fprintf(stderr, "can't open output file %s: %s\n", path,
-				strerror(errno));
-		sqlite3_finalize(ifile);
-		sqlite3_close(db);
-		return 0;
-	}
 
-	//fprintf(stderr, "uncompressing %d bytes at %p, expect %lld\n", blobsize, xzdata, (long long int)size);
+#if 0
+	fprintf(stderr, "uncompressing %d bytes at %p, expect %lld\n", blobsize, xzdata, (long long int)size);
+#endif
 	uncompresslzma(xzdata, blobsize, out);
 	close(out);
-	chmod(path, mode);
-
 	sqlite3_finalize(ifile);
 
-	return 1;
+	rc = 1;
+	if (tmpfile) {
+		if (chmod(tmpfile, mode) == -1) {
+			fprintf(stderr, "can't chmod %s: %s\n", tmpfile,
+					strerror(errno));
+			rc = 0;
+		} else if (rename(tmpfile, path) == -1) {
+			fprintf(stderr, "extract rename failed: %s\n",
+					strerror(errno));
+			rc = 0;
+		}
+	}
+
+	if (rc == 0 && tmpfile) {
+		if (unlink(tmpfile) == -1) {
+			fprintf(stderr, "unlink tmpfile %s fail: %s\n",
+					tmpfile,
+					strerror(errno));
+		}
+	}
+
+	return rc;
 }
 
 static int run_for_hash(sqlite3 *db, char *sql, char *hash) {