Make ndiscvt(8) emit the binary image array as inline assembly code rather

than a char array. Emitting the data as a big char array works fine in
the typical case, where a .sys file may be ~50K in size. Unfortunately,
some .sys files can be several hundred Kbytes in size, or even several
megabytes in size. One extreme case is the Intel centrino wireless
driver, which is 2.4MB. This causes us to emit an ndis_driver_data.h
file that's on the order of 15MB in size, and gcc consumes enormous
amounts of virtual memory while trying to compile it. On my laptop,
with 128MB of RAM and 256MB of swap space, gcc consumed all available
VM and crashed without being able to compile if_ndis.o.

By emitting the array as assembler, we bypass the C compiler and consume
much less memory. I was able to easily test compile if_ndis.ko with the
centrino driver on my laptop after this change.

This is merely a convenience, and should not have any operational effect
on the NDISulator itself.

1 files changed, 16 insertions, 8 deletions

diff --git a/usr.sbin/ndiscvt/ndiscvt.c b/usr.sbin/ndiscvt/ndiscvt.c
index a29edc4..6e34fae 100644
--- a/usr.sbin/ndiscvt/ndiscvt.c
+++ b/usr.sbin/ndiscvt/ndiscvt.c
@@ -236,25 +236,33 @@ main(int argc, char *argv[])
 		fclose(fp);
 	}
 
-	fprintf(outfp, "\n\nunsigned char drv_data[] = { \n");
+	fprintf(outfp, "\n\nextern unsigned char drv_data[];\n\n");
+
+	fprintf(outfp, "__asm__(\".data\");\n");
+	fprintf(outfp, "__asm__(\".type   drv_data, @object\");\n");
+	fprintf(outfp, "__asm__(\".size   drv_data, %d\");\n", fsize);
+	fprintf(outfp, "__asm__(\"drv_data:\");\n");
 
 	ptr = img;
 	cnt = 0;
 	while(cnt < fsize) {
-		for (i = 0; i < 12; i++) {
+		fprintf (outfp, "__asm__(\".byte ");
+		for (i = 0; i < 10; i++) {
 			cnt++;
 			if (cnt == fsize) {
-				fprintf(outfp, "0x%.2X\n", ptr[i]);
+				fprintf(outfp, "0x%.2X\");\n", ptr[i]);
 				goto done;
-			} else
-				fprintf(outfp, "0x%.2X, ", ptr[i]);
+			} else {
+				if (i == 9)
+					fprintf(outfp, "0x%.2X\");\n", ptr[i]);
+				else
+					fprintf(outfp, "0x%.2X, ", ptr[i]);
+			}
 		}
-		fprintf(outfp, "\n");
-		ptr += 12;
+		ptr += 10;
 	}
 
 done:
-	fprintf(outfp, "};\n");
 
 	if (fp != NULL)
 		fclose(fp);