certtool: better error handling in file_size()

diff --git a/src/certtool-common.c b/src/certtool-common.c
index 6729681d187ada7cf2ffc4f83459422c488a90a3..dab6c59f998e78b49c07ec33259a01eec031bee8 100644 (file)
--- a/src/certtool-common.c
+++ b/src/certtool-common.c
@@ -53,8 +53,14 @@ unsigned long lbuffer_size = 0;
 static unsigned long file_size(FILE *fp)
 {
        unsigned long size;
-       unsigned long cur = ftell(fp);
-       fseek(fp, 0, SEEK_END);
+       long cur = ftell(fp);
+
+       if (cur == -1)
+               return 0;
+
+       if (fseek(fp, 0, SEEK_END) == -1)
+               return 0;
+
        size = ftell(fp);
        fseek(fp, cur, SEEK_SET);
        return size;