detect close failure on just-written file handles

I audited git for potential undetected write failures.
In the cases fixed below, the diagnostics I add mimic the diagnostics
used in surrounding code, even when that means not reporting
the precise strerror(errno) cause of the error.

Signed-off-by: Jim Meyering <jim@meyering.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-init-db.c b/builtin-init-db.c
index 0be2d2ef6eec3e5830e893795cf9219851611859..976f47b3233cf0aba34e104bb4524aace40dccba 100644 (file)
--- a/builtin-init-db.c
+++ b/builtin-init-db.c
@@ -40,7 +40,8 @@ static int copy_file(const char *dst, const char *src, int mode)
                return fdo;
        }
        status = copy_fd(fdi, fdo);
                return fdo;
        }
        status = copy_fd(fdi, fdo);

-       close(fdo);
+       if (close(fdo) != 0)
+               return error("%s: write error: %s", dst, strerror(errno));

 
        if (!status && adjust_shared_perm(dst))
                return -1;
 
        if (!status && adjust_shared_perm(dst))
                return -1;

diff --git a/builtin-rerere.c b/builtin-rerere.c
index f6409b93c19aff7f8d820e52e39f45d717e31996..29fb075d29d2deb849e51578e2818d44dbb2a0d5 100644 (file)
--- a/builtin-rerere.c
+++ b/builtin-rerere.c
@@ -57,7 +57,8 @@ static int write_rr(struct path_list *rr, int out_fd)
                    write_in_full(out_fd, path, length) != length)
                        die("unable to write rerere record");
        }
                    write_in_full(out_fd, path, length) != length)
                        die("unable to write rerere record");
        }

-       close(out_fd);
+       if (close(out_fd) != 0)
+               die("unable to write rerere record");

        return commit_lock_file(&write_lock);
 }
 
        return commit_lock_file(&write_lock);
 }
 

diff --git a/index-pack.c b/index-pack.c
index 82c8da3683bbda15a5f7476d93c14737617d3e49..8403c36b63c041fe0c81276391a0bbea906e833d 100644 (file)
--- a/index-pack.c
+++ b/index-pack.c
@@ -634,7 +634,8 @@ static void final(const char *final_pack_name, const char *curr_pack_name,
                                write_or_die(keep_fd, keep_msg, keep_msg_len);
                                write_or_die(keep_fd, "\n", 1);
                        }
                                write_or_die(keep_fd, keep_msg, keep_msg_len);
                                write_or_die(keep_fd, "\n", 1);
                        }

-                       close(keep_fd);
+                       if (close(keep_fd) != 0)
+                               die("cannot write keep file");

                        report = "keep";
                }
        }
                        report = "keep";
                }
        }

diff --git a/refs.c b/refs.c
index 67ac97c713d071790f2d627f4c0435af23430fb8..4dc7e8b47659b75cc0dcf334f1bf33798b2e5157 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -1106,8 +1106,7 @@ static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
                len += sprintf(logrec + len - 1, "\t%.*s\n", msglen, msg) - 1;
        written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
        free(logrec);
                len += sprintf(logrec + len - 1, "\t%.*s\n", msglen, msg) - 1;
        written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
        free(logrec);

-       close(logfd);
-       if (written != len)
+       if (close(logfd) != 0 || written != len)

                return error("Unable to append to %s", log_file);
        return 0;
 }
                return error("Unable to append to %s", log_file);
        return 0;
 }


@@ -1204,8 +1203,7 @@ int create_symref(const char *ref_target, const char *refs_heads_master,
                goto error_free_return;
        }
        written = write_in_full(fd, ref, len);
                goto error_free_return;
        }
        written = write_in_full(fd, ref, len);

-       close(fd);
-       if (written != len) {
+       if (close(fd) != 0 || written != len) {

                error("Unable to write to %s", lockpath);
                goto error_unlink_return;
        }
                error("Unable to write to %s", lockpath);
                goto error_unlink_return;
        }