Rename malloc.c to alloc.c, and my master Makefile to GNUmakefile,

[sgt/agedu] / alloc.h

diff --git a/alloc.h b/alloc.h
new file mode 100644 (file)
index 0000000..654dd50
--- /dev/null
+++ b/alloc.h
@@ -0,0 +1,75 @@
+/*
+ * alloc.h: safe wrappers around malloc, realloc, free, strdup
+ */
+
+#ifndef AGEDU_ALLOC_H
+#define AGEDU_ALLOC_H
+
+#include <stddef.h>
+
+/*
+ * smalloc should guarantee to return a useful pointer.
+ */
+void *smalloc(size_t size);
+
+/*
+ * srealloc should guaranteeably be able to realloc NULL
+ */
+void *srealloc(void *p, size_t size);
+
+/*
+ * sfree should guaranteeably deal gracefully with freeing NULL
+ */
+void sfree(void *p);
+
+/*
+ * dupstr is like strdup, but with the never-return-NULL property
+ * of smalloc (and also reliably defined in all environments :-)
+ */
+char *dupstr(const char *s);
+
+/*
+ * dupfmt is a bit like printf, but does its own allocation and
+ * returns a dynamic string. It also supports a different (and
+ * much less featureful) set of format directives:
+ * 
+ *  - %D takes no argument, and gives the current date and time in
+ *    a format suitable for an HTTP Date header
+ *  - %d takes an int argument and formats it like normal %d (but
+ *    doesn't support any of the configurability of standard
+ *    printf)
+ *  - %s takes a const char * and formats it like normal %s
+ *    (again, no fine-tuning available)
+ *  - %h takes a const char * but escapes it so that it's safe for
+ *    HTML
+ *  - %S takes an int followed by a const char *. If the int is
+ *    zero, it behaves just like %s. If the int is nonzero, it
+ *    transforms the string by stuffing a \r before every \n.
+ */
+char *dupfmt(const char *fmt, ...);
+
+/*
+ * snew allocates one instance of a given type, and casts the
+ * result so as to type-check that you're assigning it to the
+ * right kind of pointer. Protects against allocation bugs
+ * involving allocating the wrong size of thing.
+ */
+#define snew(type) \
+    ( (type *) smalloc (sizeof (type)) )
+
+/*
+ * snewn allocates n instances of a given type, for arrays.
+ */
+#define snewn(number, type) \
+    ( (type *) smalloc ((number) * sizeof (type)) )
+
+/*
+ * sresize wraps realloc so that you specify the new number of
+ * elements and the type of the element, with the same type-
+ * checking advantages. Also type-checks the input pointer.
+ */
+#define sresize(array, number, type) \
+    ( (void)sizeof((array)-(type *)0), \
+      (type *) srealloc ((array), (number) * sizeof (type)) )
+
+#endif /* AGEDU_ALLOC_H */