diff: emit /dev/null if diff -rN diffs a file against /dev/null

function                                             old     new   delta
diffreg                                             1782    1786      +4
This commit is contained in:
Denis Vlasenko 2008-11-23 14:40:00 +00:00
parent 9a280fa7e6
commit 4c83025ea6

View File

@ -858,7 +858,7 @@ static void print_header(const char *file1, const char *file2)
* lines appended (beginning at b). If c is greater than d then there are
* lines missing from the to file.
*/
static void change(char *file1, FILE *f1, char *file2, FILE *f2,
static void change(const char *file1, FILE *f1, const char *file2, FILE *f2,
int a, int b, int c, int d)
{
if ((a > b && c > d) || (option_mask32 & FLAG_q)) {
@ -902,7 +902,7 @@ static void change(char *file1, FILE *f1, char *file2, FILE *f2,
}
static void output(char *file1, FILE *f1, char *file2, FILE *f2)
static void output(const char *file1, FILE *f1, const char *file2, FILE *f2)
{
/* Note that j0 and j1 can't be used as they are defined in math.h.
* This also allows the rather amusing variable 'j00'... */
@ -999,7 +999,7 @@ static void output(char *file1, FILE *f1, char *file2, FILE *f2)
*/
/* NB: files can be not REGular. The only sure thing that they
* are not both DIRectories. */
static unsigned diffreg(char *file1, char *file2, int flags)
static unsigned diffreg(const char *file1, const char *file2, int flags)
{
int *member; /* will be overlaid on nfile[1] */
int *class; /* will be overlaid on nfile[0] */
@ -1022,12 +1022,10 @@ static unsigned diffreg(char *file1, char *file2, int flags)
if (flags & D_EMPTY1)
/* can't be stdin, but xfopen_stdin() is smaller code */
f1 = xfopen_stdin(bb_dev_null);
else
file1 = bb_dev_null;
f1 = xfopen_stdin(file1);
if (flags & D_EMPTY2)
f2 = xfopen_stdin(bb_dev_null);
else
file2 = bb_dev_null;
f2 = xfopen_stdin(file2);
/* NB: if D_EMPTY1/2 is set, other file is always a regular file,