Make extension-replacement a utility function in file.c (as it will need to

be performed for the list file, etc, as well as the object file).

svn path=/trunk/yasm/; revision=381

frontends/yasm/yasm.c

@@ -27,6 +27,7 @@
 #endif
 
 #include "bitvect.h"
+#include "file.h"
 
 #include "globals.h"
 #include "options.h"
@@ -139,20 +140,12 @@ main(int argc, char *argv[])
     /* open the object file if not specified */
     if (!obj) {
 	/* build the object filename */
-	char *exttail;
 	if (obj_filename)
 	    xfree(obj_filename);
 	assert(in_filename != NULL);
-	/* allocate enough space for full existing name + extension */
-	obj_filename = xmalloc(strlen(in_filename)+
-			       strlen(cur_objfmt->extension)+2);
-	strcpy(obj_filename, in_filename);
-	exttail = strrchr(obj_filename, '.');
-	if (!exttail)
-	    exttail = strrchr(obj_filename, '\0');
-	/*@-nullpass@*/
-	sprintf(exttail, ".%s", cur_objfmt->extension);
-	/*@=nullpass@*/
+	/* replace (or add) extension */
+	obj_filename = replace_extension(in_filename, cur_objfmt->extension,
+					 "yasm.out");
 
 	/* open the built filename */
 	obj = fopen(obj_filename, "wb");

libyasm/file.c

@@ -24,6 +24,49 @@
 
 #include "file.h"
 
+#include "errwarn.h"
+
+
+char *
+replace_extension(const char *orig, const char *ext, const char *def)
+{
+    char *out, *outext;
+
+    /* allocate enough space for full existing name + extension */
+    out = xmalloc(strlen(orig)+strlen(ext)+2);
+    strcpy(out, orig);
+    outext = strrchr(out, '.');
+    if (outext) {
+	/* Existing extension: make sure it's not the same as the replacement
+	 * (as we don't want to overwrite the source file).
+	 */
+	outext++;   /* advance past '.' */
+	if (strcmp(outext, ext)) {
+	    outext = NULL;  /* indicate default should be used */
+	    WarningNow(_("file name already ends in `.%s': output will be in `%s'"),
+		       ext, def);
+	}
+    } else {
+	/* No extension: make sure the output extension is not empty
+	 * (again, we don't want to overwrite the source file).
+	 */
+	if (*ext == '\0')
+	    WarningNow(_("file name already has no extension: output will be in `%s'"),
+		       def);
+	else {
+	    outext = strrchr(out, '\0');    /* point to end of the string */
+	    *outext++ = '.';		    /* append '.' */
+	}
+    }
+
+    /* replace extension or use default name */
+    if (outext)
+	strcpy(outext, ext);
+    else
+	strcpy(out, def);
+
+    return out;
+}
 
 size_t
 fwrite_short(unsigned short val, FILE *f)

libyasm/file.h

@@ -22,6 +22,13 @@
 #ifndef YASM_FILE_H
 #define YASM_FILE_H
 
+/* Replace extension on a filename (or append one if none is present).
+ * If output filename would be identical to input (same extension out as in),
+ * returns (copy of) def.
+ */
+/*@only@*/ char *replace_extension(const char *orig, const char *ext,
+				   const char *def);
+
 /* These functions only work properly if p is an (unsigned char *) */
 
 #define WRITE_BYTE(ptr, val)			\

src/file.c

@@ -24,6 +24,49 @@
 
 #include "file.h"
 
+#include "errwarn.h"
+
+
+char *
+replace_extension(const char *orig, const char *ext, const char *def)
+{
+    char *out, *outext;
+
+    /* allocate enough space for full existing name + extension */
+    out = xmalloc(strlen(orig)+strlen(ext)+2);
+    strcpy(out, orig);
+    outext = strrchr(out, '.');
+    if (outext) {
+	/* Existing extension: make sure it's not the same as the replacement
+	 * (as we don't want to overwrite the source file).
+	 */
+	outext++;   /* advance past '.' */
+	if (strcmp(outext, ext)) {
+	    outext = NULL;  /* indicate default should be used */
+	    WarningNow(_("file name already ends in `.%s': output will be in `%s'"),
+		       ext, def);
+	}
+    } else {
+	/* No extension: make sure the output extension is not empty
+	 * (again, we don't want to overwrite the source file).
+	 */
+	if (*ext == '\0')
+	    WarningNow(_("file name already has no extension: output will be in `%s'"),
+		       def);
+	else {
+	    outext = strrchr(out, '\0');    /* point to end of the string */
+	    *outext++ = '.';		    /* append '.' */
+	}
+    }
+
+    /* replace extension or use default name */
+    if (outext)
+	strcpy(outext, ext);
+    else
+	strcpy(out, def);
+
+    return out;
+}
 
 size_t
 fwrite_short(unsigned short val, FILE *f)

src/file.h

@@ -22,6 +22,13 @@
 #ifndef YASM_FILE_H
 #define YASM_FILE_H
 
+/* Replace extension on a filename (or append one if none is present).
+ * If output filename would be identical to input (same extension out as in),
+ * returns (copy of) def.
+ */
+/*@only@*/ char *replace_extension(const char *orig, const char *ext,
+				   const char *def);
+
 /* These functions only work properly if p is an (unsigned char *) */
 
 #define WRITE_BYTE(ptr, val)			\

src/main.c

@@ -27,6 +27,7 @@
 #endif
 
 #include "bitvect.h"
+#include "file.h"
 
 #include "globals.h"
 #include "options.h"
@@ -139,20 +140,12 @@ main(int argc, char *argv[])
     /* open the object file if not specified */
     if (!obj) {
 	/* build the object filename */
-	char *exttail;
 	if (obj_filename)
 	    xfree(obj_filename);
 	assert(in_filename != NULL);
-	/* allocate enough space for full existing name + extension */
-	obj_filename = xmalloc(strlen(in_filename)+
-			       strlen(cur_objfmt->extension)+2);
-	strcpy(obj_filename, in_filename);
-	exttail = strrchr(obj_filename, '.');
-	if (!exttail)
-	    exttail = strrchr(obj_filename, '\0');
-	/*@-nullpass@*/
-	sprintf(exttail, ".%s", cur_objfmt->extension);
-	/*@=nullpass@*/
+	/* replace (or add) extension */
+	obj_filename = replace_extension(in_filename, cur_objfmt->extension,
+					 "yasm.out");
 
 	/* open the built filename */
 	obj = fopen(obj_filename, "wb");