From 581133ecce7f868b9aeab5eede7da0e2a995b1d6 Mon Sep 17 00:00:00 2001
From: "Anthony J. Bentley" <anthony@anjbe.name>
Date: Fri, 11 Dec 2015 01:06:19 -0700
Subject: [PATCH] Output make-style dependencies with -M.

---
 src/asm/fstack.c |  6 ++++++
 src/asm/main.c   | 18 ++++++++++++++++--
 src/asm/rgbasm.1 |  5 +++++
 3 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/src/asm/fstack.c b/src/asm/fstack.c
index 56fc46d0..dbbf2bb3 100644
--- a/src/asm/fstack.c
+++ b/src/asm/fstack.c
@@ -36,6 +36,9 @@ ULONG nCurrentREPTBlockCount;
 
 ULONG ulMacroReturnValue;
 
+extern char *tzObjectname;
+extern FILE *dependfile;
+
 /*
  * defines for nCurrentStatus
  */
@@ -190,6 +193,9 @@ fstk_FindFile(char *fname)
 	FILE *f;
 
 	if ((f = fopen(fname, "rb")) != NULL || errno != ENOENT) {
+		if (dependfile) {
+			fprintf(dependfile, "%s: %s\n", tzObjectname, fname);
+		}
 		return f;
 	}
 
diff --git a/src/asm/main.c b/src/asm/main.c
index 99a7cc39..cc2c1315 100644
--- a/src/asm/main.c
+++ b/src/asm/main.c
@@ -28,6 +28,9 @@ ULONG nTotalLines, nPass, nPC, nIFDepth, nErrors;
 
 extern int yydebug;
 
+FILE *dependfile;
+extern char *tzObjectname;
+
 /*
  * Option stack
  */
@@ -258,7 +261,7 @@ usage(void)
 {
 	printf(
 "Usage: rgbasm [-hv] [-b chars] [-Dname[=value]] [-g chars] [-i path]\n"
-"              [-o outfile] [-p pad_value] file.asm\n");
+"              [-M dependfile] [-o outfile] [-p pad_value] file.asm\n");
 	exit(1);
 }
 
@@ -272,6 +275,8 @@ main(int argc, char *argv[])
 
 	char *tzMainfile;
 
+	dependfile = NULL;
+
 	cldefines_size = 32;
 	cldefines = reallocarray(cldefines, cldefines_size,
 	                        2 * sizeof(void *));
@@ -301,7 +306,7 @@ main(int argc, char *argv[])
 
 	newopt = CurrentOptions;
 
-	while ((ch = getopt(argc, argv, "b:D:g:hi:o:p:v")) != -1) {
+	while ((ch = getopt(argc, argv, "b:D:g:hi:M:o:p:v")) != -1) {
 		switch (ch) {
 		case 'b':
 			if (strlen(optarg) == 2) {
@@ -332,6 +337,11 @@ main(int argc, char *argv[])
 		case 'i':
 			fstk_AddIncludePath(optarg);
 			break;
+		case 'M':
+			if ((dependfile = fopen(optarg, "w")) == NULL) {
+				err(1, "Could not open dependfile %s", optarg);
+			}
+			break;
 		case 'o':
 			out_SetFileName(optarg);
 			break;
@@ -370,6 +380,10 @@ main(int argc, char *argv[])
 		printf("Assembling %s\n", tzMainfile);
 	}
 
+	if (dependfile) {
+		fprintf(dependfile, "%s: %s\n", tzObjectname, tzMainfile);
+	}
+
 	nStartClock = clock();
 
 	nLineNo = 1;
diff --git a/src/asm/rgbasm.1 b/src/asm/rgbasm.1
index 9434729a..a8cef72e 100644
--- a/src/asm/rgbasm.1
+++ b/src/asm/rgbasm.1
@@ -45,6 +45,11 @@ The
 option disables this behavior.
 .It Fl i Ar path
 Add an include path.
+.It Fl M Ar dependfile
+Print
+.Xr make 1
+dependencies to
+.Ar dependfile .
 .It Fl o Ar outfile
 Write an object file to the given filename.
 .It Fl p Ar pad_value