Merge #1896 'Fix coverity issues. (3)'

1 files changed, 23 insertions, 6 deletions

diff --git a/src/nvim/os_unix.c b/src/nvim/os_unix.c
index f7b47f9569..d674db951f 100644
--- a/src/nvim/os_unix.c
+++ b/src/nvim/os_unix.c
@@ -13,6 +13,7 @@
  * changed beyond recognition.
  */
 
+#include <assert.h>
 #include <errno.h>
 #include <inttypes.h>
 #include <stdbool.h>
@@ -1158,14 +1159,30 @@ int mch_expand_wildcards(int num_pat, char_u **pat, int *num_file,
     free(tempname);
     goto notfound;
   }
-  fseek(fd, 0L, SEEK_END);
-  len = ftell(fd);                      /* get size of temp file */
+  int fseek_res = fseek(fd, 0L, SEEK_END);
+  if (fseek_res < 0) {
+    free(tempname);
+    fclose(fd);
+    return FAIL;
+  }
+  long long templen = ftell(fd);        /* get size of temp file */
+  if (templen < 0) {
+    free(tempname);
+    fclose(fd);
+    return FAIL;
+  }
+#if SIZEOF_LONG_LONG > SIZEOF_SIZE_T
+  assert(templen <= (long long)SIZE_MAX);
+#endif
+  len = (size_t)templen;
   fseek(fd, 0L, SEEK_SET);
   buffer = xmalloc(len + 1);
-  i = fread((char *)buffer, 1, len, fd);
+  // fread() doesn't terminate buffer with NUL;
+  // appropiate termination (not always NUL) is done below.
+  size_t readlen = fread((char *)buffer, 1, len, fd);
   fclose(fd);
   os_remove((char *)tempname);
-  if (i != (int)len) {
+  if (readlen != len) {
     /* unexpected read error */
     EMSG2(_(e_notread), tempname);
     free(tempname);
@@ -1174,8 +1191,6 @@ int mch_expand_wildcards(int num_pat, char_u **pat, int *num_file,
   }
   free(tempname);
 
-
-
   /* file names are separated with Space */
   if (shell_style == STYLE_ECHO) {
     buffer[len] = '\n';                 /* make sure the buffer ends in NL */
@@ -1235,6 +1250,8 @@ int mch_expand_wildcards(int num_pat, char_u **pat, int *num_file,
     if (len)
       ++i;                              /* count last entry */
   }
+  assert(buffer[len] == NUL || buffer[len] == '\n');
+
   if (i == 0) {
     /*
      * Can happen when using /bin/sh and typing ":e $NO_SUCH_VAR^I".