#include <h/nmh.h>
+/* It's undefined behaviour in C99 to convert from a function pointer to
+ * a data-object pointer, e.g. void pointer. gcc's -pedantic warns of
+ * this and can stop compilation. POSIX requires the operation however,
+ * e.g. for dlsym(3), and so we know it's safe on POSIX platforms, e.g.
+ * the pointers are of the same size. Thus use a union to subvert gcc's
+ * check. The function-pointer equivalent of a void pointer is any
+ * function-pointer type as all function pointers are defined to be
+ * convertible from one another; use the simplest available. */
+typedef union {
+ void *v;
+ void (*f)(void);
+} generic_pointer;
+
/*
* Well-used constants
*/
*/
#define NMH_BUFSIZ max(BUFSIZ, 8192)
-#ifndef FALSE
-#define FALSE false
-#endif
-#ifndef TRUE
-#define TRUE true
-#endif
-typedef unsigned char boolean; /* not int so we can pack in a structure */
-
/* If we're using gcc then tell it extra information so it can do more
* compile-time checks. */
#if __GNUC__ > 2
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
-#define ALLOC_SIZE(...) __attribute__((alloc_size(__VA_ARGS__)))
-#define CHECK_PRINTF(fmt, arg) __attribute__((format(printf, fmt, arg)))
-#else /* gcc < 4.3.0 */
-#define ALLOC_SIZE(...)
-#define CHECK_PRINTF(fmt, arg)
-#endif /* gcc < 4.3.0 */
#define NORETURN __attribute__((__noreturn__))
#define CONST __attribute__((const))
#define MALLOC __attribute__((malloc))
#define NONNULL(...) __attribute__((nonnull(__VA_ARGS__)))
#define PURE __attribute__((pure))
#define ENDNULL __attribute__((sentinel))
-#define NMH_UNUSED(i) (void) i
#else
#define NORETURN
#define CHECK_PRINTF(fmt, arg)
#define NONNULL(...)
#define PURE
#define ENDNULL
-#define NMH_UNUSED(i) i
#endif
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
+#define ALLOC_SIZE(...) __attribute__((alloc_size(__VA_ARGS__)))
+#define CHECK_PRINTF(fmt, arg) __attribute__((format(printf, fmt, arg)))
+#else
+#define ALLOC_SIZE(...)
+#define CHECK_PRINTF(fmt, arg)
+#endif
+
+/* Silence the compiler's "unused variable" warning. */
+#define NMH_UNUSED(i) (void)i
+
/* DIM gives the number of elements in the one-dimensional array a. */
#define DIM(a) (sizeof (a) / sizeof (*(a)))
char *sw;
- /* The minchars field is apparently used like this:
+ /*
+ * The previous comments here about minchars was incorrect; this is
+ * (AFAIK) the correct information.
+ *
+ * A minchars of "0" means this switch can be abbreviated to any number
+ * of characters (assuming the abbreviation does not match any other
+ * switches).
+ *
+ * A positive value for minchars means that when the user specifies
+ * the switch on the command line, it MUST be at least that many
+ * characters.
+ *
+ * A negative value for minchars means that the user-given switch must
+ * be that many characters, but will NOT be shown in -help output.
+ *
+ * So what should I use? Well, for nearly all switches you want to specify
+ * a minchars of 0. smatch will report an error if the switch given
+ * matches more than one entry. Let's say you have the following
+ * two switches: -append and -apply. -app will return AMBIGSW from
+ * smatch. -appe and -appl will work fine. So 0 is the correct choice
+ * here.
+ *
+ * The only time you want to specify a minimum length is if you have
+ * a switch who's name is a substring of a longer switch. The example
+ * you see sometimes in the code is -form and -format. If you gave a
+ * minchars of 0 for both, -form would match both -form AND -format,
+ * and you'd always get AMBIGSW. The solution is to specify a minchars
+ * of 5 for -format; that way just -form will just match -form. When
+ * a minchars is given, the -help output will specify the minimum
+ * switch length, like this:
+ *
+ * -(forma)t string
+ *
+ * A negative value works the same way, except the switch isn't printed
+ * in -help. Why would you do that? Well, there are a few instances
+ * of internal switches and some switches which only appear if a particular
+ * feature is enabled (such as SASL or TLS). Lately I've been of the
+ * opinion that all switches should be specified, even if they are
+ * internal or use non-available features, but currently the smatch
+ * code still supports this.
+ *
+ * This isn't the appropriate place to make this note, but since I was
+ * here ... when creating switches, you should make a negation switch
+ * right after the enabling switch. E.g. you should have:
+ *
+ * X("sasl", 0, SASLSW) \
+ * X("nosasl", 0, NOSASLSW) \
+ *
+ * in the switch array, because when you run -help, print_sw will detect
+ * this and output:
+ *
+ * -[no]sasl
+ */
- -# : Switch can be abbreviated to # characters; switch hidden in -help.
- 0 : Switch can't be abbreviated; switch shown in -help.
- # : Switch can be abbreviated to # characters; switch shown in -help. */
int minchars;
/*
extern char *whatnowproc;
extern char *whomproc;
-extern void (*done) (int) NORETURN;
-
#include <h/prototypes.h>
projects / nmh / blobdiff