4624

Start requiring a '-o' flag to designate the output binary when translating.

Things currently get funky if you pass in multiple inputs, but that's ok.
This is the first step to supporting multiple input files for a single
output binary.

19 files changed, 58 insertions, 31 deletions

diff --git a/subx/001help.cc b/subx/001help.cc
index efb3ac46..bf06aee3 100644
--- a/subx/001help.cc
+++ b/subx/001help.cc
@@ -73,7 +73,7 @@ void init_help() {
     "    subx --help\n"
     "- Convert a textual SubX program into a standard ELF binary that you can\n"
     "  run on your computer:\n"
-    "    subx translate <input 'source' file> <output ELF binary>\n"
+    "    subx translate <input 'source' file> -o <output ELF binary>\n"
     "- Run a SubX binary using SubX itself (for better error messages):\n"
     "    subx run <ELF binary>\n"
     "Add '--trace' to any of these commands to also emit a trace, for debugging purposes.\n"
diff --git a/subx/028translate.cc b/subx/028translate.cc
index 174a863a..303d6219 100644
--- a/subx/028translate.cc
+++ b/subx/028translate.cc
@@ -19,30 +19,57 @@
 :(before "End Main")
 if (is_equal(argv[1], "translate")) {
   START_TRACING_UNTIL_END_OF_SCOPE;
-  assert(argc > 3);
   reset();
   program p;
-  ifstream fin(argv[2]);
-  if (!fin) {
-    cerr << "could not open " << argv[2] << '\n';
-    return 1;
+  string output_filename;
+  for (int i = /*skip 'subx translate'*/2;  i < argc;  ++i) {
+    if (is_equal(argv[i], "-o")) {
+      ++i;
+      if (i >= argc) {
+        print_translate_usage();
+        cerr << "'-o' must be followed by a filename to write results to\n";
+        exit(1);
+      }
+      output_filename = argv[i];
+    }
+    else {
+      ifstream fin(argv[i]);
+      if (!fin) {
+        cerr << "could not open " << argv[i] << '\n';
+        return 1;
+      }
+      parse(fin, p);
+      if (trace_contains_errors()) return 1;
+    }
+  }
+  if (p.segments.empty()) {
+    print_translate_usage();
+    cerr << "nothing to do; must provide at least one file to read\n";
+    exit(1);
+  }
+  if (output_filename.empty()) {
+    print_translate_usage();
+    cerr << "must provide a filename to write to using '-o'\n";
+    exit(1);
   }
-  parse(fin, p);
-  if (trace_contains_errors()) return 1;
   transform(p);
   if (trace_contains_errors()) return 1;
-  save_elf(p, argv[3]);
+  save_elf(p, output_filename);
   if (trace_contains_errors()) {
-    unlink(argv[3]);
+    unlink(output_filename.c_str());
     return 1;
   }
   return 0;
 }
 
 :(code)
+void print_translate_usage() {
+  cerr << "Usage: subx translate <input.subx> -o <output_ELF>\n";
+}
+
 // write out a program to a bare-bones ELF file
-void save_elf(const program& p, const char* filename) {
-  ofstream out(filename, ios::binary);
+void save_elf(const program& p, const string& filename) {
+  ofstream out(filename.c_str(), ios::binary);
   write_elf_header(out, p);
   for (size_t i = 0;  i < p.segments.size();  ++i)
     write_segment(p.segments.at(i), out);
diff --git a/subx/Readme.md b/subx/Readme.md
index 67a7e5e1..baba8e1b 100644
--- a/subx/Readme.md
+++ b/subx/Readme.md
@@ -111,7 +111,7 @@ Running `subx` will transparently compile it as necessary.
 
 * `subx test`: runs all automated tests.
 
-* `subx translate <input file> <output ELF binary>`: translates a text file
+* `subx translate <input file> -o <output ELF binary>`: translates a text file
   containing hex bytes and macros into an executable ELF binary.
 
 * `subx run <ELF binary>`: simulates running the ELF binaries emitted by `subx
@@ -123,7 +123,7 @@ Putting them together, build and run one of the example programs:
 <img alt='apps/factorial.subx' src='../html/subx/factorial.png'>
 
 ```
-$ ./subx translate apps/factorial.subx apps/factorial
+$ ./subx translate apps/factorial.subx -o apps/factorial
 $ ./subx run apps/factorial  # returns the factorial of 5
 $ echo $?
 120  
diff --git a/subx/apps/crenshaw2-1.subx b/subx/apps/crenshaw2-1.subx
index b1df5889..ef0ee70e 100644
--- a/subx/apps/crenshaw2-1.subx
+++ b/subx/apps/crenshaw2-1.subx
@@ -2,7 +2,7 @@
 # corresponds to the section "single digits" in https://compilers.iecc.com/crenshaw/tutor2.txt
 #
 # To run:
-#   $ subx translate apps/crenshaw2.1.subx crenshaw 2.1
+#   $ subx translate apps/crenshaw2.1.subx -o crenshaw 2.1
 #   $ echo '3'  |subx run apps/crenshaw2.1  |xxd -
 # Expected output:
 #   TODO
diff --git a/subx/apps/factorial.subx b/subx/apps/factorial.subx
index b4f8867e..80ff7418 100644
--- a/subx/apps/factorial.subx
+++ b/subx/apps/factorial.subx
@@ -1,7 +1,7 @@
 ## compute the factorial of 5, and return the result in the exit code
 #
 # To run:
-#   $ subx translate apps/factorial.subx apps/factorial
+#   $ subx translate apps/factorial.subx -o apps/factorial
 #   $ subx run apps/factorial
 # Expected result:
 #   $ echo $?
diff --git a/subx/examples/ex1.subx b/subx/examples/ex1.subx
index a355ef6b..ae909777 100644
--- a/subx/examples/ex1.subx
+++ b/subx/examples/ex1.subx
@@ -2,7 +2,7 @@
 # Just return 42.
 #
 # To run:
-#   $ subx translate ex1.2.subx ex1
+#   $ subx translate ex1.2.subx -o ex1
 #   $ subx run ex1
 # Expected result:
 #   $ echo $?
diff --git a/subx/examples/ex10.subx b/subx/examples/ex10.subx
index 92e9f1f4..64a92f2c 100644
--- a/subx/examples/ex10.subx
+++ b/subx/examples/ex10.subx
@@ -1,7 +1,7 @@
 ## String comparison: return 1 iff the two args passed in at the commandline are equal.
 #
 # To run:
-#   $ subx translate ex10.subx ex10
+#   $ subx translate ex10.subx -o ex10
 #   $ subx run ex10 abc abd
 # Expected result:
 #   $ echo $?
diff --git a/subx/examples/ex11.subx b/subx/examples/ex11.subx
index 8c2c9625..0159be69 100644
--- a/subx/examples/ex11.subx
+++ b/subx/examples/ex11.subx
@@ -6,7 +6,7 @@
 # (length-prefixed) literal string "target".
 #
 # To run:
-#   $ subx translate ex11.subx ex11
+#   $ subx translate ex11.subx -o ex11
 #   $ subx run ex11  # runs a series of tests
 #   ......  # all tests pass
 #
diff --git a/subx/examples/ex12.subx b/subx/examples/ex12.subx
index 50c57928..86250d4d 100644
--- a/subx/examples/ex12.subx
+++ b/subx/examples/ex12.subx
@@ -2,7 +2,7 @@
 # Create a new segment using mmap, save the address, write to it.
 #
 # To run:
-#   $ subx translate ex12.subx ex12
+#   $ subx translate ex12.subx -o ex12
 #   $ subx run ex12
 # You shouldn't get a segmentation fault.
 
diff --git a/subx/examples/ex2.subx b/subx/examples/ex2.subx
index e0c76712..62294b83 100644
--- a/subx/examples/ex2.subx
+++ b/subx/examples/ex2.subx
@@ -1,7 +1,7 @@
 ## add 1 and 1, and return the result in the exit code
 #
 # To run:
-#   $ subx translate ex2.subx ex2
+#   $ subx translate ex2.subx -o ex2
 #   $ subx run ex2
 # Expected result:
 #   $ echo $?
diff --git a/subx/examples/ex3.subx b/subx/examples/ex3.subx
index 30a8d5d3..50edd923 100644
--- a/subx/examples/ex3.subx
+++ b/subx/examples/ex3.subx
@@ -1,7 +1,7 @@
 ## add the first 10 numbers, and return the result in the exit code
 #
 # To run:
-#   $ subx translate ex3.subx ex3
+#   $ subx translate ex3.subx -o ex3
 #   $ subx run ex3
 # Expected result:
 #   $ echo $?
diff --git a/subx/examples/ex4.subx b/subx/examples/ex4.subx
index 810278e6..89926a62 100644
--- a/subx/examples/ex4.subx
+++ b/subx/examples/ex4.subx
@@ -1,7 +1,7 @@
 ## read a character from stdin, save it to a global, write it to stdout
 #
 # To run:
-#   $ subx translate ex4.subx ex4
+#   $ subx translate ex4.subx -o ex4
 #   $ subx run ex4
 
 == code
diff --git a/subx/examples/ex5.subx b/subx/examples/ex5.subx
index 51bc19a0..e00289a2 100644
--- a/subx/examples/ex5.subx
+++ b/subx/examples/ex5.subx
@@ -1,7 +1,7 @@
 ## read a character from stdin, save it to a local on the stack, write it to stdout
 #
 # To run:
-#   $ subx translate ex5.subx ex5
+#   $ subx translate ex5.subx -o ex5
 #   $ subx run ex5
 
 == code
diff --git a/subx/examples/ex6.subx b/subx/examples/ex6.subx
index 0213ad7e..f9adcc5a 100644
--- a/subx/examples/ex6.subx
+++ b/subx/examples/ex6.subx
@@ -1,7 +1,7 @@
 ## print out a (global variable) string to stdout
 #
 # To run:
-#   $ subx translate ex6.subx ex6
+#   $ subx translate ex6.subx -o ex6
 #   $ subx run ex6
 #   Hello, world!
 
diff --git a/subx/examples/ex7.subx b/subx/examples/ex7.subx
index a1bb19c8..b6dc639a 100644
--- a/subx/examples/ex7.subx
+++ b/subx/examples/ex7.subx
@@ -4,7 +4,7 @@
 # the character read.
 #
 # To run:
-#   $ subx translate ex8.subx ex8
+#   $ subx translate ex8.subx -o ex8
 #   $ subx run ex8
 # Expected result:
 #   $ echo $?
diff --git a/subx/examples/ex8.subx b/subx/examples/ex8.subx
index 1a094b89..ba0ddcd3 100644
--- a/subx/examples/ex8.subx
+++ b/subx/examples/ex8.subx
@@ -1,7 +1,7 @@
 ## Example reading commandline arguments: compute length of first arg.
 #
 # To run:
-#   $ subx translate ex8.subx ex8
+#   $ subx translate ex8.subx -o ex8
 #   $ subx run ex8 abc de fghi
 # Expected result:
 #   $ echo $?
diff --git a/subx/examples/ex9.subx b/subx/examples/ex9.subx
index 8c0fba29..3590839f 100644
--- a/subx/examples/ex9.subx
+++ b/subx/examples/ex9.subx
@@ -3,7 +3,7 @@
 # letter of second arg.
 #
 # To run:
-#   $ subx translate ex9.subx ex9
+#   $ subx translate ex9.subx -o ex9
 #   $ subx run ex9 z x
 # Expected result:
 #   $ echo $?
diff --git a/subx/gen b/subx/gen
index 464506b3..a73d763b 100755
--- a/subx/gen
+++ b/subx/gen
@@ -3,9 +3,9 @@
 
 if [[ $1 == 'ex'* ]]
 then
-  CFLAGS=-g subx translate examples/$1.subx examples/`echo $1 |sed 's/\..*//'`
+  CFLAGS=-g subx translate examples/$1.subx -o examples/`echo $1 |sed 's/\..*//'`
   exit $?
 fi
 
-CFLAGS=-g subx translate apps/$1.subx apps/`echo $1 |sed 's/\..*//'`
+CFLAGS=-g subx translate apps/$1.subx -o apps/`echo $1 |sed 's/\..*//'`
 exit $?
diff --git a/subx/test_layers b/subx/test_layers
index 12867b21..b1a2b3a6 100755
--- a/subx/test_layers
+++ b/subx/test_layers
@@ -15,7 +15,7 @@ for f in examples/ex*.subx apps/*.subx
 do
   echo checking $f
   target=`echo $f |sed 's/\..*//'`
-  CFLAGS=-g ./subx translate $f $target
+  CFLAGS=-g ./subx translate $f -o $target
   git diff --quiet $target  ||  exit 1
   echo $target generated as expected
 done