Add dry run feature

4 files changed, 38 insertions, 15 deletions

diff --git a/README b/README
index a6efd38..f2a8bf3 100644
--- a/README
+++ b/README
@@ -4,7 +4,7 @@ nsgenbind
 This is a tool to generate JavaScript to DOM bindings from w3c webidl
 files and a binding configuration file.
 
-building
+Building
 --------
 
 The tool requires bison and flex as pre-requisites
@@ -12,29 +12,33 @@ The tool requires bison and flex as pre-requisites
 Commandline
 -----------
 
-nsgenbind [-v] [-g] [-D] [-W] [-I idlpath] inputfile outputdir
+nsgenbind [-v] [-n] [-g] [-D] [-W] [-I idlpath] inputfile outputdir
 
 -v
-The verbose switch makes the tool verbose about what operations it is
-performing instead of the default of only reporting errors.
+  The verbose switch makes the tool verbose about what operations it
+   is performing instead of the default of only reporting errors.
+
+-n
+  The tool will not generate any output but will perform all other
+   operations as if it was. Useful for debugging bindings
 
 -g
-The generated code will be augmented with runtime debug logging so it
-can be traced
+  The generated code will be augmented with runtime debug logging so
+   it can be traced
 
 -D
-The tool will generate output to allow debugging of output conversion.
-This includes dumps of the binding and IDL files AST
+  The tool will generate output to allow debugging of output
+   conversion.  This includes dumps of the binding and IDL files AST
 
 -W
-This switch will make the tool generate warnings about various issues
-with the binding or IDL files being processed.
+  This switch will make the tool generate warnings about various
+   issues with the binding or IDL files being processed.
 
 -I
-An additional search path may be given so idl files can be located.
+  An additional search path may be given so idl files can be located.
 
 The tool requires a binding file as input and an output directory in
-which to place its output.
+ which to place its output.
 
 
 Debug output
diff --git a/src/nsgenbind.c b/src/nsgenbind.c
index 173f23d..9558b95 100644
--- a/src/nsgenbind.c
+++ b/src/nsgenbind.c
@@ -39,7 +39,7 @@ static struct options* process_cmdline(int argc, char **argv)
                 return NULL;
         }
 
-        while ((opt = getopt(argc, argv, "vgDW::I:")) != -1) {
+        while ((opt = getopt(argc, argv, "vngDW::I:")) != -1) {
                 switch (opt) {
                 case 'I':
                         options->idlpath = strdup(optarg);
@@ -49,6 +49,10 @@ static struct options* process_cmdline(int argc, char **argv)
                         options->verbose = true;
                         break;
 
+                case 'n':
+                        options->dryrun = true;
+                        break;
+
                 case 'D':
                         options->debug = true;
                         break;
diff --git a/src/options.h b/src/options.h
index 02674b7..5b7d73d 100644
--- a/src/options.h
+++ b/src/options.h
@@ -18,6 +18,8 @@ struct options {
 	bool verbose; /**< verbose processing */
 	bool debug; /**< debug enabled */
 	bool dbglog; /**< embed debug logging in output */
+        bool dryrun; /**< output is not generated */
+
 	unsigned int warnings; /**< warning flags */
 };
 
diff --git a/src/utils.c b/src/utils.c
index 0952744..85d26f2 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -48,7 +48,11 @@ FILE *genb_fopen(const char *fname, const char *mode)
         char *fpath;
         FILE *filef;
 
-        fpath = genb_fpath(fname);
+        if (options->dryrun) {
+                fpath = strdup("/dev/null");
+        } else {
+                fpath = genb_fpath(fname);
+        }
 
         filef = fopen(fpath, mode);
         if (filef == NULL) {
@@ -68,7 +72,11 @@ FILE *genb_fopen_tmp(const char *fname)
         char *fpath;
         FILE *filef;
 
-        fpath = genb_fpath_tmp(fname);
+        if (options->dryrun) {
+                fpath = strdup("/dev/null");
+        } else {
+                fpath = genb_fpath_tmp(fname);
+        }
 
         filef = fopen(fpath, "w+");
         if (filef == NULL) {
@@ -92,6 +100,11 @@ int genb_fclose_tmp(FILE *filef_tmp, const char *fname)
         size_t trd;
         size_t frd;
 
+        if (options->dryrun) {
+                fclose(filef_tmp);
+                return 0;
+        }
+
         fpath = genb_fpath(fname);
         tpath = genb_fpath_tmp(fname);