diff: implement --binary flag

On Windows GNU diff uses text mode for input and output.  It also
has the '--binary' flag to use binary mode instead.  On Unix binary
mode is the default and the flag does nothing.

Alter diff to use text mode by default for input (though not output,
let's not go overboard).  Add the '--binary' flag to override this.

Costs 96-160 bytes.

1 files changed, 25 insertions, 0 deletions

diff --git a/editors/diff.c b/editors/diff.c
index 17d41af8d..d91ecea51 100644
--- a/editors/diff.c
+++ b/editors/diff.c
@@ -119,6 +119,9 @@
 //usage:     "\n        -t      Expand tabs to spaces in output"
 //usage:     "\n        -U      Output LINES lines of context"
 //usage:     "\n        -w      Ignore all whitespace"
+//usage:        IF_PLATFORM_MINGW32(IF_FEATURE_DIFF_LONG_OPTIONS(
+//usage:     "\n        --binary  Treat input as binary, not text"
+//usage:        ))
 
 #include "libbb.h"
 #include "common_bufsiz.h"
@@ -154,6 +157,9 @@ enum {                  /* Commandline flags */
         FLAG_p,         /* not implemented */
         FLAG_B,
         FLAG_E,         /* not implemented */
+#if ENABLE_PLATFORM_MINGW32
+        FLAG_binary,
+#endif
 };
 #define FLAG(x) (1 << FLAG_##x)
 
@@ -720,7 +726,12 @@ static int diffreg(char *file[2])
                 int fd = STDIN_FILENO;
                 if (!LONE_DASH(file[i])) {
                         if (!(option_mask32 & FLAG(N))) {
+#if ENABLE_PLATFORM_MINGW32
+                                int flag = (option_mask32 & FLAG(binary)) ? 0 : _O_TEXT;
+                                fd = open_or_warn(file[i], O_RDONLY | flag);
+#else
                                 fd = open_or_warn(file[i], O_RDONLY);
+#endif
                                 if (fd == -1)
                                         goto out;
                         } else {
@@ -751,10 +762,21 @@ static int diffreg(char *file[2])
                                 xfunc_die();
                         if (fd != STDIN_FILENO)
                                 close(fd);
+#if ENABLE_PLATFORM_MINGW32
+                        if (!(option_mask32 & FLAG(binary))) {
+                                /* Close and reopen tmpfile to get text mode */
+                                close(fd_tmp);
+                                fd_tmp = xopen(tmpfile[i], O_RDONLY | _O_TEXT);
+                        }
+#endif
                         fd = fd_tmp;
                         xlseek(fd, 0, SEEK_SET);
                 }
+#if ENABLE_PLATFORM_MINGW32
+                fp[i] = fdopen(fd, (option_mask32 & FLAG(binary)) ? "r" : "rt");
+#else
                 fp[i] = fdopen(fd, "r");
+#endif
         }
 
         setup_common_bufsiz();
@@ -985,6 +1007,9 @@ static const char diff_longopts[] ALIGN1 =
         "report-identical-files\0"   No_argument       "s"
         "starting-file\0"            Required_argument "S"
         "minimal\0"                  No_argument       "d"
+#if ENABLE_PLATFORM_MINGW32
+        "binary\0"                   No_argument       "\xff"
+#endif
         ;
 # define GETOPT32 getopt32long
 # define LONGOPTS ,diff_longopts