libctf: new test of enum lookups with the _next iterator

I had reports that this doesn't work.  This test shows it working (and
also shows how annoying it is to do symbol lookup by name with the
present API: we need a ctf_arc_lookup_symbol_name for users that don't
already have a symtab handy).

libctf/ChangeLog
2021-01-05  Nick Alcock  <nick.alcock@oracle.com>

	* testsuite/libctf-lookup/enum-symbol.lk: New symbol-lookup test.
	* testsuite/libctf-lookup/enum-symbol-ctf.c: New CTF input.
	* testsuite/libctf-lookup/enum-symbol.c: New lookup test.

libctf/ChangeLog

@@ -1,3 +1,9 @@
+2021-01-05  Nick Alcock  <nick.alcock@oracle.com>
+
+	* testsuite/libctf-lookup/enum-symbol.lk: New symbol-lookup test.
+	* testsuite/libctf-lookup/enum-symbol-ctf.c: New CTF input.
+	* testsuite/libctf-lookup/enum-symbol.c: New lookup test.
+
 2021-01-05  Nick Alcock  <nick.alcock@oracle.com>
 
 	* Makefile.am (EXPECT): New.

libctf/testsuite/libctf-lookup/enum-symbol-ctf.c

@@ -0,0 +1 @@
+enum {red1, green1, blue1} primary1;

libctf/testsuite/libctf-lookup/enum-symbol.c

@@ -0,0 +1,153 @@
+#include "config.h"
+#include <bfd.h>
+#include <elf.h>
+#include <ctf-api.h>
+#include <swap.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+ssize_t symidx_64 (ctf_sect_t *s, ctf_sect_t *strsect, int little_endian, const char *name)
+{
+  const char *strs = (const char *) strsect->cts_data;
+  size_t i;
+  Elf64_Sym *sym = (Elf64_Sym *) s->cts_data;
+  for (i = 0; i < s->cts_size / s->cts_entsize; i++, sym++)
+    {
+      Elf64_Word nameoff = sym->st_name;
+#ifdef WORDS_BIGENDIAN
+      if (little_endian)
+	swap_thing (nameoff);
+#else
+      if (!little_endian)
+	swap_thing (nameoff);
+#endif
+      if (strcmp (strs + nameoff, name) == 0)
+	return i;
+    }
+  return -1;
+}
+
+ssize_t symidx_32 (ctf_sect_t *s, ctf_sect_t *strsect, int little_endian, const char *name)
+{
+  const char *strs = (const char *) strsect->cts_data;
+  size_t i;
+  Elf32_Sym *sym = (Elf32_Sym *) s->cts_data;
+  for (i = 0; i < s->cts_size / s->cts_entsize; i++, sym++)
+    {
+      Elf32_Word nameoff = sym->st_name;
+#ifdef WORDS_BIGENDIAN
+      if (little_endian)
+	swap_thing (nameoff);
+#else
+      if (!little_endian)
+	swap_thing (nameoff);
+#endif
+      if (strcmp (strs + nameoff, name) == 0)
+	return i;
+    }
+  return -1;
+}
+
+int
+main (int argc, char *argv[])
+{
+  ctf_dict_t *fp;
+  bfd *abfd;
+  ctf_archive_t *ctf;
+  ctf_sect_t symsect;
+  ctf_sect_t strsect;
+  ssize_t symidx;
+  int err;
+  ctf_id_t type;
+  ctf_next_t *i = NULL;
+  const char *name;
+  int val;
+  int little_endian;
+
+  ssize_t (*get_sym) (ctf_sect_t *s, ctf_sect_t *strsect, int little_endian, const char *name);
+
+  if (argc != 2)
+    {
+      fprintf (stderr, "Syntax: %s PROGRAM\n", argv[0]);
+      exit(1);
+    }
+
+  /* Figure out the endianness of the symtab(s).  */
+  if ((abfd = bfd_openr (argv[1], NULL)) == NULL
+      || !bfd_check_format (abfd, bfd_object))
+    goto bfd_open_err;
+  little_endian = bfd_little_endian (abfd);
+  bfd_close_all_done (abfd);
+
+  if ((ctf = ctf_open (argv[1], NULL, &err)) == NULL)
+    goto open_err;
+
+  if ((fp = ctf_dict_open (ctf, NULL, &err)) == NULL)
+    goto open_err;
+
+  symsect = ctf_getsymsect (fp);
+  strsect = ctf_getstrsect (fp);
+  if (symsect.cts_data == NULL
+      || strsect.cts_data == NULL)
+    {
+      fprintf (stderr, "%s: no symtab or strtab\n", argv[0]);
+      return 1;
+    }
+
+  ctf_dict_close (fp);
+
+  if (symsect.cts_entsize != sizeof (Elf64_Sym) &&
+      symsect.cts_entsize != sizeof (Elf32_Sym))
+    {
+      fprintf (stderr, "%s: unknown symsize: %lx\n", argv[0],
+	       symsect.cts_size);
+      return 1;
+    }
+
+  switch (symsect.cts_entsize)
+    {
+    case sizeof (Elf64_Sym): get_sym = symidx_64; break;
+    case sizeof (Elf32_Sym): get_sym = symidx_32; break;
+    }
+
+  if ((symidx = get_sym (&symsect, &strsect, little_endian, "primary1")) < 0)
+    {
+      fprintf (stderr, "%s: symbol not found: primary1\n", argv[0]);
+      return 1;
+    }
+
+  /* Fish it out, then fish out all its enumerand/value pairs.  */
+
+  if ((fp = ctf_arc_lookup_symbol (ctf, symidx, &type, &err)) == NULL)
+    goto sym_err;
+
+  while ((name = ctf_enum_next (fp, type, &i, &val)) != NULL)
+    {
+      printf ("%s has value %i\n", name, val);
+    }
+  if (ctf_errno (fp) != ECTF_NEXT_END)
+    goto nerr;
+
+  ctf_dict_close (fp);
+  ctf_close (ctf);
+
+  return 0;
+
+ bfd_open_err:
+  fprintf (stderr, "%s: cannot open: %s\n", argv[0], bfd_errmsg (bfd_get_error ()));
+  return 1;
+
+ open_err:
+  fprintf (stderr, "%s: cannot open: %s\n", argv[0], ctf_errmsg (err));
+  return 1;
+ sym_err:
+  fprintf (stderr, "%s: Symbol lookup error: %s\n", argv[0], ctf_errmsg (err));
+  return 1;
+ err:
+  fprintf (stderr, "Lookup failed: %s\n", ctf_errmsg (ctf_errno (fp)));
+  return 1;
+ nerr:
+  fprintf (stderr, "iteration failed: %s\n", ctf_errmsg (ctf_errno (fp)));
+  return 1;
+}

libctf/testsuite/libctf-lookup/enum-symbol.lk

@@ -0,0 +1,6 @@
+# lookup: enum-symbol.c
+# source: enum-symbol-ctf.c
+# link: on
+red1 has value 0
+green1 has value 1
+blue1 has value 2