lib: put printfrr extension args into struct

... for easier extensibility.  Add width, # and - flags while at it.

Signed-off-by: David Lamparter <equinox@diac24.net>

bgpd/bgp_table.c

@@ -201,8 +201,8 @@ struct bgp_node *bgp_table_subtree_lookup(const struct bgp_table *table,
 }
 
 printfrr_ext_autoreg_p("BD", printfrr_bd)
-static ssize_t printfrr_bd(struct fbuf *buf, const char **fmt,
-			   int prec, const void *ptr)
+static ssize_t printfrr_bd(struct fbuf *buf, struct printfrr_eargs *ea,
+			   const void *ptr)
 {
 	const struct bgp_dest *dest = ptr;
 	const struct prefix *p = bgp_dest_get_prefix(dest);

lib/nexthop.c

@@ -730,22 +730,22 @@ int nexthop_str2backups(const char *str, int *num_backups,
  *		nexthop2str()
  */
 printfrr_ext_autoreg_p("NH", printfrr_nh)
-static ssize_t printfrr_nh(struct fbuf *buf, const char **fmt,
-			   int prec, const void *ptr)
+static ssize_t printfrr_nh(struct fbuf *buf, struct printfrr_eargs *ea,
+			   const void *ptr)
 {
 	const struct nexthop *nexthop = ptr;
 	bool do_ifi = false;
 	const char *v_is = "", *v_via = "", *v_viaif = "via ";
 	ssize_t ret = 0;
 
-	switch (**fmt) {
+	switch (*ea->fmt) {
 	case 'v':
-		(*fmt)++;
-		if (**fmt == 'v') {
+		ea->fmt++;
+		if (*ea->fmt == 'v') {
 			v_is = "is ";
 			v_via = "via ";
 			v_viaif = "";
-			(*fmt)++;
+			ea->fmt++;
 		}
 
 		if (!nexthop)
@@ -796,7 +796,7 @@ static ssize_t printfrr_nh(struct fbuf *buf, const char **fmt,
 
 		return ret;
 	case 's':
-		(*fmt)++;
+		ea->fmt++;
 
 		if (!nexthop)
 			return bputs(buf, "(null)");

lib/prefix.c

@@ -1361,8 +1361,8 @@ char *evpn_es_df_alg2str(uint8_t df_alg, char *buf, int buf_len)
 }
 
 printfrr_ext_autoreg_p("EA", printfrr_ea)
-static ssize_t printfrr_ea(struct fbuf *buf, const char **fmt,
-			   int prec, const void *ptr)
+static ssize_t printfrr_ea(struct fbuf *buf, struct printfrr_eargs *ea,
+			   const void *ptr)
 {
 	const struct ethaddr *mac = ptr;
 	char cbuf[ETHER_ADDR_STRLEN];
@@ -1376,8 +1376,8 @@ static ssize_t printfrr_ea(struct fbuf *buf, const char **fmt,
 }
 
 printfrr_ext_autoreg_p("IA", printfrr_ia)
-static ssize_t printfrr_ia(struct fbuf *buf, const char **fmt,
-			   int prec, const void *ptr)
+static ssize_t printfrr_ia(struct fbuf *buf, struct printfrr_eargs *ea,
+			   const void *ptr)
 {
 	const struct ipaddr *ipa = ptr;
 	char cbuf[INET6_ADDRSTRLEN];
@@ -1390,8 +1390,8 @@ static ssize_t printfrr_ia(struct fbuf *buf, const char **fmt,
 }
 
 printfrr_ext_autoreg_p("I4", printfrr_i4)
-static ssize_t printfrr_i4(struct fbuf *buf, const char **fmt,
-			   int prec, const void *ptr)
+static ssize_t printfrr_i4(struct fbuf *buf, struct printfrr_eargs *ea,
+			   const void *ptr)
 {
 	char cbuf[INET_ADDRSTRLEN];
 
@@ -1403,8 +1403,8 @@ static ssize_t printfrr_i4(struct fbuf *buf, const char **fmt,
 }
 
 printfrr_ext_autoreg_p("I6", printfrr_i6)
-static ssize_t printfrr_i6(struct fbuf *buf, const char **fmt,
-			   int prec, const void *ptr)
+static ssize_t printfrr_i6(struct fbuf *buf, struct printfrr_eargs *ea,
+			   const void *ptr)
 {
 	char cbuf[INET6_ADDRSTRLEN];
 
@@ -1416,8 +1416,8 @@ static ssize_t printfrr_i6(struct fbuf *buf, const char **fmt,
 }
 
 printfrr_ext_autoreg_p("FX", printfrr_pfx)
-static ssize_t printfrr_pfx(struct fbuf *buf, const char **fmt,
-			    int prec, const void *ptr)
+static ssize_t printfrr_pfx(struct fbuf *buf, struct printfrr_eargs *ea,
+			    const void *ptr)
 {
 	char cbuf[PREFIX_STRLEN];
 
@@ -1429,8 +1429,8 @@ static ssize_t printfrr_pfx(struct fbuf *buf, const char **fmt,
 }
 
 printfrr_ext_autoreg_p("SG4", printfrr_psg)
-static ssize_t printfrr_psg(struct fbuf *buf, const char **fmt,
-			    int prec, const void *ptr)
+static ssize_t printfrr_psg(struct fbuf *buf, struct printfrr_eargs *ea,
+			    const void *ptr)
 {
 	const struct prefix_sg *sg = ptr;
 	ssize_t ret = 0;

lib/printf/glue.c

@@ -210,10 +210,10 @@ void printfrr_ext_reg(const struct printfrr_ext *ext)
 	exts[i] = ext;
 }
 
-ssize_t printfrr_extp(struct fbuf *buf, const char **fmtp, int prec,
+ssize_t printfrr_extp(struct fbuf *buf, struct printfrr_eargs *ea,
 		      const void *ptr)
 {
-	const char *fmt = *fmtp;
+	const char *fmt = ea->fmt;
 	const struct printfrr_ext *ext;
 	size_t i;
 
@@ -227,16 +227,16 @@ ssize_t printfrr_extp(struct fbuf *buf, const char **fmtp, int prec,
 			continue;
 		if (strncmp(ext->match, fmt, strlen(ext->match)))
 			continue;
-		*fmtp += strlen(ext->match);
-		return ext->print_ptr(buf, fmtp, prec, ptr);
+		ea->fmt += strlen(ext->match);
+		return ext->print_ptr(buf, ea, ptr);
 	}
 	return -1;
 }
 
-ssize_t printfrr_exti(struct fbuf *buf, const char **fmtp, int prec,
+ssize_t printfrr_exti(struct fbuf *buf, struct printfrr_eargs *ea,
 		      uintmax_t num)
 {
-	const char *fmt = *fmtp;
+	const char *fmt = ea->fmt;
 	const struct printfrr_ext *ext;
 	size_t i;
 
@@ -250,8 +250,8 @@ ssize_t printfrr_exti(struct fbuf *buf, const char **fmtp, int prec,
 			continue;
 		if (strncmp(ext->match, fmt, strlen(ext->match)))
 			continue;
-		*fmtp += strlen(ext->match);
-		return ext->print_int(buf, fmtp, prec, num);
+		ea->fmt += strlen(ext->match);
+		return ext->print_int(buf, ea, num);
 	}
 	return -1;
 }

lib/printf/printflocal.h

@@ -101,6 +101,7 @@ int	_frr_find_warguments(const wchar_t *, va_list, union arg **) DSO_LOCAL;
 #endif
 
 /* returns number of bytes needed for full output, or -1 */
-ssize_t printfrr_extp(struct fbuf *, const char **, int, const void *)
+ssize_t printfrr_extp(struct fbuf *, struct printfrr_eargs *ea, const void *)
+	DSO_LOCAL;
+ssize_t printfrr_exti(struct fbuf *, struct printfrr_eargs *ea, uintmax_t)
 	DSO_LOCAL;
-ssize_t printfrr_exti(struct fbuf *, const char **, int, uintmax_t) DSO_LOCAL;

lib/printf/vfprintf.c

@@ -456,14 +456,25 @@ reswitch:	switch (ch) {
 				ulval = SARG();
 
 			if (printfrr_ext_char(fmt[0])) {
+				struct printfrr_eargs ea = {
+					.fmt = fmt,
+					.precision = prec,
+					.width = width,
+					.alt_repr = !!(flags & ALT),
+					.leftadj = !!(flags & LADJUST),
+				};
+
 				if (cb)
 					extstart = cb->pos;
 
-				size = printfrr_exti(cb, &fmt, prec,
+				size = printfrr_exti(cb, &ea,
 						(flags & INTMAX_SIZE) ? ujval
 						: (uintmax_t)ulval);
-				if (size >= 0)
+				if (size >= 0) {
+					fmt = ea.fmt;
+					width = ea.width;
 					goto ext_printed;
+				}
 			}
 			if (flags & INTMAX_SIZE) {
 				if ((intmax_t)ujval < 0) {
@@ -539,12 +550,23 @@ reswitch:	switch (ch) {
 			 */
 			ptrval = GETARG(void *);
 			if (printfrr_ext_char(fmt[0])) {
+				struct printfrr_eargs ea = {
+					.fmt = fmt,
+					.precision = prec,
+					.width = width,
+					.alt_repr = !!(flags & ALT),
+					.leftadj = !!(flags & LADJUST),
+				};
+
 				if (cb)
 					extstart = cb->pos;
 
-				size = printfrr_extp(cb, &fmt, prec, ptrval);
-				if (size >= 0)
+				size = printfrr_extp(cb, &ea, ptrval);
+				if (size >= 0) {
+					fmt = ea.fmt;
+					width = ea.width;
 					goto ext_printed;
+				}
 			}
 			ujval = (uintmax_t)(uintptr_t)ptrval;
 			base = 16;

lib/printfrr.h

@@ -112,6 +112,8 @@ char  *asnprintfrr(struct memtype *mt, char *out, size_t sz,
  */
 #define printfrr_ext_char(ch) ((ch) >= 'A' && (ch) <= 'Z')
 
+struct printfrr_eargs;
+
 struct printfrr_ext {
 	/* embedded string to minimize cache line pollution */
 	char match[8];
@@ -127,14 +129,53 @@ struct printfrr_ext {
 	 * to consume extra input flags after %pXY, increment *fmt.  It points
 	 * at the first character after %pXY at entry.  Convention is to make
 	 * those flags lowercase letters or numbers.
+	 */
+	ssize_t (*print_ptr)(struct fbuf *buf, struct printfrr_eargs *info,
+			     const void *);
+	ssize_t (*print_int)(struct fbuf *buf, struct printfrr_eargs *info,
+			     uintmax_t);
+};
+
+/* additional information passed to extended formatters */
+
+struct printfrr_eargs {
+	/* position in the format string.  Points to directly after the
+	 * extension specifier.  Increment when consuming extra "flag
+	 * characters".
+	 */
+	const char *fmt;
+
+	/* %.1234x / %.*x
+	 * not POSIX compatible when used with %p, will cause warnings from
+	 * GCC & clang.  Usable with %d.  Not used by the printfrr() itself
+	 * for extension specifiers, so essentially available as a "free"
+	 * parameter.  -1 if not specified.  Value in the format string
+	 * cannot be negative, but negative values can be passed with %.*x
+	 */
+	int precision;
+
+	/* %1234x / %*x
+	 * regular width specification.  Internally handled by printfrr(), set
+	 * to 0 if consumed by the extension in order to suppress standard
+	 * width/padding behavior.  0 if not specified.
 	 *
-	 * prec is the precision specifier (the 999 in "%.999p")  -1 means
-	 * none given (value in the format string cannot be negative)
+	 * NB: always positive, even if a negative value is passed in with
+	 * %*x.  (The sign is used for the - flag.)
+	 */
+	int width;
+
+	/* %#x
+	 * "alternate representation" flag, not POSIX compatible when used
+	 * with %p or %d, will cause warnings from GCC & clang.  Not used by
+	 * printfrr() itself for extension specifiers.
+	 */
+	bool alt_repr;
+
+	/* %-x
+	 * left-pad flag.  Internally handled by printfrr() if width is
+	 * nonzero.  Only use if the extension sets width to 0.
 	 */
-	ssize_t (*print_ptr)(struct fbuf *buf, const char **fmt, int prec,
-			const void *);
-	ssize_t (*print_int)(struct fbuf *buf, const char **fmt, int prec,
-			uintmax_t);
+	bool leftadj;
 };
 
 /* no locking - must be called when single threaded (e.g. at startup.)
@@ -144,7 +185,7 @@ struct printfrr_ext {
 void printfrr_ext_reg(const struct printfrr_ext *);
 
 #define printfrr_ext_autoreg_p(matchs, print_fn)                               \
-	static ssize_t print_fn(struct fbuf *, const char **, int,             \
+	static ssize_t print_fn(struct fbuf *, struct printfrr_eargs *,        \
 				const void *);                                 \
 	static const struct printfrr_ext _printext_##print_fn = {              \
 		.match = matchs,                                               \
@@ -157,7 +198,8 @@ void printfrr_ext_reg(const struct printfrr_ext *);
 	/* end */
 
 #define printfrr_ext_autoreg_i(matchs, print_fn)                               \
-	static ssize_t print_fn(struct fbuf *, const char **, int, uintmax_t); \
+	static ssize_t print_fn(struct fbuf *, struct printfrr_eargs *,        \
+				uintmax_t);                                    \
 	static const struct printfrr_ext _printext_##print_fn = {              \
 		.match = matchs,                                               \
 		.print_int = print_fn,                                         \

lib/sockunion.c

@@ -664,8 +664,8 @@ void sockunion_init(union sockunion *su)
 }
 
 printfrr_ext_autoreg_p("SU", printfrr_psu)
-static ssize_t printfrr_psu(struct fbuf *buf, const char **fmt,
-			    int prec, const void *ptr)
+static ssize_t printfrr_psu(struct fbuf *buf, struct printfrr_eargs *ea,
+			    const void *ptr)
 {
 	const union sockunion *su = ptr;
 	bool include_port = false;
@@ -677,9 +677,9 @@ static ssize_t printfrr_psu(struct fbuf *buf, const char **fmt,
 		return bputs(buf, "(null)");
 
 	while (!endflags) {
-		switch (**fmt) {
+		switch (*ea->fmt) {
 		case 'p':
-			(*fmt)++;
+			ea->fmt++;
 			include_port = true;
 			break;
 		default:

lib/srcdest_table.c

@@ -307,8 +307,8 @@ const char *srcdest_rnode2str(const struct route_node *rn, char *str, int size)
 }
 
 printfrr_ext_autoreg_p("RN", printfrr_rn)
-static ssize_t printfrr_rn(struct fbuf *buf, const char **fmt,
-			   int prec, const void *ptr)
+static ssize_t printfrr_rn(struct fbuf *buf, struct printfrr_eargs *ea,
+			   const void *ptr)
 {
 	const struct route_node *rn = ptr;
 	const struct prefix *dst_p, *src_p;