From cf459ca16fb22ff0542442512a3b5c7b7899d7b4 Mon Sep 17 00:00:00 2001
From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Tue, 16 Apr 2019 14:26:11 -0300
Subject: [PATCH] fprintf: Pretty print struct members that are pointers to
 nameless structs

I.e. to structs defined inside other structs, without a name:

Before:

  $ pahole -C parsed_partitions /home/acme/git/build/v5.1-rc4+/block/partitions/check.o
  struct parsed_partitions {
  	struct block_device *      bdev;                 /*     0     8 */
  	char                       name[32];             /*     8    32 */
  	struct  *                  parts;                /*    40     8 */
  	int                        next;                 /*    48     4 */
  	int                        limit;                /*    52     4 */
  	bool                       access_beyond_eod;    /*    56     1 */

  	/* XXX 7 bytes hole, try to pack */

  	/* --- cacheline 1 boundary (64 bytes) --- */
  	char *                     pp_buf;               /*    64     8 */

  	/* size: 72, cachelines: 2, members: 7 */
  	/* sum members: 65, holes: 1, sum holes: 7 */
  	/* last cacheline: 8 bytes */
  };
  $

After:

  $ pahole -C parsed_partitions /home/acme/git/build/v5.1-rc4+/block/partitions/check.o
  struct parsed_partitions {
  	struct block_device * bdev;                      /*     0     8 */
  	char                       name[32];             /*     8    32 */
  	struct {
  		sector_t           from;                 /*    40     8 */
  		sector_t           size;                 /*    48     8 */
  		int                flags;                /*    56     4 */
  		bool               has_info;             /*    60     1 */
  		struct partition_meta_info info;         /*    61   101 */
  	} * parts; /*    40     8 */
  	int                        next;                 /*    48     4 */
  	int                        limit;                /*    52     4 */
  	bool                       access_beyond_eod;    /*    56     1 */

  	/* XXX 7 bytes hole, try to pack */

  	/* --- cacheline 1 boundary (64 bytes) --- */
  	char *                     pp_buf;               /*    64     8 */

  	/* size: 72, cachelines: 2, members: 7 */
  	/* sum members: 65, holes: 1, sum holes: 7 */
  	/* last cacheline: 8 bytes */
  };
  $

Still need to align that offsets, leave this for later.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 dwarves_fprintf.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/dwarves_fprintf.c b/dwarves_fprintf.c
index 492bd66..98bb476 100644
--- a/dwarves_fprintf.c
+++ b/dwarves_fprintf.c
@@ -595,6 +595,7 @@ static size_t type__fprintf(struct tag *type, const struct cu *cu,
 {
 	char tbf[128];
 	char namebf[256];
+	char namebfptr[258];
 	struct type *ctype;
 	struct conf_fprintf tconf;
 	size_t printed = 0;
@@ -673,6 +674,7 @@ static size_t type__fprintf(struct tag *type, const struct cu *cu,
 
 	if (tag__is_struct(type) || tag__is_union(type) ||
 	    tag__is_enumeration(type)) {
+inner_struct:
 		tconf.type_spacing -= 8;
 		tconf.prefix	   = NULL;
 		tconf.suffix	   = name;
@@ -698,6 +700,13 @@ next_type:
 							  &tconf, fp);
 				break;
 			}
+			if (tag__is_struct(ptype) || tag__is_union(ptype) ||
+			    tag__is_enumeration(ptype)) {
+				snprintf(namebfptr, sizeof(namebfptr), "* %s", name);
+				name = namebfptr;
+				type = ptype;
+				goto inner_struct;
+			}
 		}
 		/* Fall Thru */
 	default: