Junio C HamanoWhen diff-cache -p and friends are interrupted, they can leave their temporary files behind. Also when the external diff program is killed instead of exiting (this usually happens when piping the output to a pager, which can cause SIGPIPE when the user quits viewing the diff early), they incorrectly died without cleaning their temporary file. This patch fixes these problems.
Signed-off-by: Junio C Hamano <junkio@cox.net> ---
diff.c | 29 ++++++++++++++++++++++++----- 1 files changed, 24 insertions(+), 5 deletions(-)
# - [PATCH] diff-tree -p implies diff-tree -p -r # + 04/27 21:50 diff.c clean up temporary file. --- k/diff.c +++ l/diff.c
Show changes to diff +24 −5
@@ -3,6 +3,7 @@ */ #include <sys/types.h> #include <sys/wait.h> +#include <signal.h> #include "cache.h" #include "diff.h" @@ -119,6 +120,9 @@ static void prepare_temp_file(const char if (!one->file_valid) { not_a_valid_file: + /* A '-' entry produces this for file-2, and + * a '+' entry produces this for file-1. + */ temp->name = "/dev/null"; strcpy(temp->hex, "."); strcpy(temp->mode, "."); @@ -139,7 +143,7 @@ static void prepare_temp_file(const char goto not_a_valid_file; die("stat(%s): %s", temp->name, strerror(errno)); } - strcpy(temp->hex, "."); + strcpy(temp->hex, sha1_to_hex(null_sha1)); sprintf(temp->mode, "%06o", S_IFREG |ce_permissions(st.st_mode)); } @@ -180,6 +184,11 @@ static void remove_tempfile(void) } } +static void remove_tempfile_on_signal(int signo) +{ + remove_tempfile(); +} + /* An external diff command takes: * * diff-cmd name infile1 infile1-sha1 infile1-mode \ @@ -191,7 +200,8 @@ void run_external_diff(const char *name, struct diff_spec *two) { struct diff_tempfile *temp = diff_temp; - int pid, status; + pid_t pid; + int status; static int atexit_asked = 0; if (one && two) { @@ -203,6 +213,7 @@ void run_external_diff(const char *name, atexit_asked = 1; atexit(remove_tempfile); } + signal(SIGINT, remove_tempfile_on_signal); } fflush(NULL); @@ -230,9 +241,17 @@ void run_external_diff(const char *name, printf("* Unmerged path %s\n", name); exit(0); } - if (waitpid(pid, &status, 0) < 0 || !WIFEXITED(status)) - die("diff program failed"); - + if (waitpid(pid, &status, 0) < 0 || !WIFEXITED(status)) { + /* We do not check the exit status because typically + * diff exits non-zero if files are different, and + * we are not interested in knowing that. We *knew* + * they are different and that's why we ran diff + * in the first place! However if it dies by a signal, + * we stop processing immediately. + */ + remove_tempfile(); + die("external diff died unexpectedly.\n"); + } remove_tempfile(); }