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GNU libavl 2.0.1

5.14.6 Utility Functions

The first utility function is compare_ints(). This function is not used by <@xref{\NODE\, , test.c.>,97} but it is included there because it is used by the test modules for all the individual tree structures.

/* Utility functions. */ <@xref{\NODE\, , Comparison function for int.>s,3}

See also @refalso{136 This code is included in @refalso{97

It is prototyped in <@xref{\NODE\, , test.h.>,99}:

int compare_ints (const void *pa, const void *pb, void *param);

The fail() function prints a provided error message to stderr, formatting it as with printf(), and terminates the program unsuccessfully:

/* Prints message on stderr, which is formatted as for printf(), and terminates the program unsuccessfully. */ static void fail (const char *message, ...) { va_list args; fprintf (stderr, "%s:", pgm_name); va_start (args, message); vfprintf (stderr, message, args); va_end (args); putchar ('\n'); exit (EXIT_FAILURE); }

Finally, the xmalloc() function is a malloc() wrapper that aborts the program if allocation fails:

/* Allocates and returns a pointer to size bytes of memory. Aborts if allocation fails. */ static void * xmalloc (size_t size) { void *block = malloc (size); if (block == NULL && size != 0) fail ("outofmemory"); return block; }