Moving in the library source from the mpg123lib branch.

git-svn-id: svn://scm.orgis.org/mpg123/trunk@998 35dc7657-300d-0410-a2e5-dc2837fedb53

src/libmpg123/stringbuf.c

@@ -0,0 +1,94 @@
+/*
+	stringbuf: mimicking a bit of C++ to more safely handle strings
+
+	copyright 2006-7 by the mpg123 project - free software under the terms of the LGPL 2.1
+	see COPYING and AUTHORS files in distribution or http://mpg123.org
+	initially written by Thomas Orgis
+*/
+
+#include "config.h"
+#include "debug.h"
+#include "mpg123.h"
+#include <stdlib.h>
+#include <string.h>
+
+void mpg123_init_string(mpg123_string* sb)
+{
+	sb->p = NULL;
+	sb->size = 0;
+	sb->fill = 0;
+}
+
+void mpg123_free_string(mpg123_string* sb)
+{
+	if(sb->p != NULL) free(sb->p);
+	mpg123_init_string(sb);
+}
+
+int mpg123_resize_string(mpg123_string* sb, size_t new)
+{
+	debug3("resizing string pointer %p from %lu to %lu", (void*) sb->p, (unsigned long)sb->size, (unsigned long)new);
+	if(new == 0)
+	{
+		if(sb->size && sb->p != NULL) free(sb->p);
+		mpg123_init_string(sb);
+		return 1;
+	}
+	if(sb->size != new)
+	{
+		char* t;
+		debug("really!");
+		t = (char*) realloc(sb->p, new*sizeof(char));
+		debug1("realloc returned %p", (void*) t); 
+		if(t != NULL)
+		{
+			sb->p = t;
+			sb->size = new;
+			return 1;
+		}
+		else return 0;
+	}
+	else return 1; /* success */
+}
+
+int mpg123_copy_string(mpg123_string* from, mpg123_string* to)
+{
+	if(mpg123_resize_string(to, from->fill))
+	{
+		memcpy(to->p, from->p, to->size);
+		to->fill = to->size;
+		return 1;
+	}
+	else return 0;
+}
+
+int mpg123_add_string(mpg123_string* sb, char* stuff)
+{
+	size_t addl = strlen(stuff)+1;
+	debug1("adding %s", stuff);
+	if(sb->fill)
+	{
+		if(sb->size >= sb->fill-1+addl || mpg123_resize_string(sb, sb->fill-1+addl))
+		{
+			memcpy(sb->p+sb->fill-1, stuff, addl);
+			sb->fill += addl-1;
+		}
+		else return 0;
+	}
+	else
+	{
+		if(mpg123_resize_string(sb, addl))
+		{
+			memcpy(sb->p, stuff, addl);
+			sb->fill = addl;
+		}
+		else return 0;
+	}
+	return 1;
+}
+
+int mpg123_set_string(mpg123_string* sb, char* stuff)
+{
+	sb->fill = 0;
+	return mpg123_add_string(sb, stuff);
+}