libctf/ctf-impl.h

   1 /* Implementation header.
   2    Copyright (C) 2019 Free Software Foundation, Inc.
   3
   4    This file is part of libctf.
   5
   6    libctf is free software; you can redistribute it and/or modify it under
   7    the terms of the GNU General Public License as published by the Free
   8    Software Foundation; either version 3, or (at your option) any later
   9    version.
  10
  11    This program is distributed in the hope that it will be useful, but
  12    WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  14    See the GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; see the file COPYING.  If not see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _CTF_IMPL_H
  21 #define _CTF_IMPL_H
  22
  23 #include "config.h"
  24 #include <sys/errno.h>
  25 #include <ctf-api.h>
  26 #include <sys/types.h>
  27 #include <stdlib.h>
  28 #include <stdarg.h>
  29 #include <stdio.h>
  30 #include <stdint.h>
  31 #include <limits.h>
  32 #include <ctype.h>
  33 #include <elf.h>
  34 #include <bfd.h>
  35
  36 #ifdef  __cplusplus
  37 extern "C"
  38   {
  39 #endif
  40
  41 /* Compiler attributes.  */
  42
  43 #if defined (__GNUC__)
  44
  45 /* GCC.  We assume that all compilers claiming to be GCC support sufficiently
  46    many GCC attributes that the code below works.  If some non-GCC compilers
  47    masquerading as GCC in fact do not implement these attributes, version checks
  48    may be required.  */
  49
  50 /* We use the _libctf_*_ pattern to avoid clashes with any future attribute
  51    macros glibc may introduce, which have names of the pattern
  52    __attribute_blah__.  */
  53
  54 #define _libctf_printflike_(string_index,first_to_check) \
  55     __attribute__ ((__format__ (__printf__, (string_index), (first_to_check))))
  56 #define _libctf_unlikely_(x) __builtin_expect ((x), 0)
  57 #define _libctf_unused_ __attribute__ ((__unused__))
  58 #define _libctf_malloc_ __attribute__((__malloc__))
  59
  60 #endif
  61
  62 /* libctf in-memory state.  */
  63
  64 typedef struct ctf_fixed_hash ctf_hash_t; /* Private to ctf-hash.c.  */
  65 typedef struct ctf_dynhash ctf_dynhash_t; /* Private to ctf-hash.c.  */
  66
  67 typedef struct ctf_strs
  68 {
  69   const char *cts_strs;         /* Base address of string table.  */
  70   size_t cts_len;               /* Size of string table in bytes.  */
  71 } ctf_strs_t;
  72
  73 typedef struct ctf_dmodel
  74 {
  75   const char *ctd_name;         /* Data model name.  */
  76   int ctd_code;                 /* Data model code.  */
  77   size_t ctd_pointer;           /* Size of void * in bytes.  */
  78   size_t ctd_char;              /* Size of char in bytes.  */
  79   size_t ctd_short;             /* Size of short in bytes.  */
  80   size_t ctd_int;               /* Size of int in bytes.  */
  81   size_t ctd_long;              /* Size of long in bytes.  */
  82 } ctf_dmodel_t;
  83
  84 typedef struct ctf_lookup
  85 {
  86   const char *ctl_prefix;       /* String prefix for this lookup.  */
  87   size_t ctl_len;               /* Length of prefix string in bytes.  */
  88   ctf_hash_t *ctl_hash;         /* Pointer to hash table for lookup.  */
  89 } ctf_lookup_t;
  90
  91 typedef struct ctf_fileops
  92 {
  93   uint32_t (*ctfo_get_kind) (uint32_t);
  94   uint32_t (*ctfo_get_root) (uint32_t);
  95   uint32_t (*ctfo_get_vlen) (uint32_t);
  96   ssize_t (*ctfo_get_ctt_size) (const ctf_file_t *, const ctf_type_t *,
  97                                 ssize_t *, ssize_t *);
  98   ssize_t (*ctfo_get_vbytes) (unsigned short, ssize_t, size_t);
  99 } ctf_fileops_t;
 100
 101 typedef struct ctf_list
 102 {
 103   struct ctf_list *l_prev;      /* Previous pointer or tail pointer.  */
 104   struct ctf_list *l_next;      /* Next pointer or head pointer.  */
 105 } ctf_list_t;
 106
 107 typedef enum
 108   {
 109    CTF_PREC_BASE,
 110    CTF_PREC_POINTER,
 111    CTF_PREC_ARRAY,
 112    CTF_PREC_FUNCTION,
 113    CTF_PREC_MAX
 114   } ctf_decl_prec_t;
 115
 116 typedef struct ctf_decl_node
 117 {
 118   ctf_list_t cd_list;           /* Linked list pointers.  */
 119   ctf_id_t cd_type;             /* Type identifier.  */
 120   uint32_t cd_kind;             /* Type kind.  */
 121   uint32_t cd_n;                /* Type dimension if array.  */
 122 } ctf_decl_node_t;
 123
 124 typedef struct ctf_decl
 125 {
 126   ctf_list_t cd_nodes[CTF_PREC_MAX]; /* Declaration node stacks.  */
 127   int cd_order[CTF_PREC_MAX];        /* Storage order of decls.  */
 128   ctf_decl_prec_t cd_qualp;          /* Qualifier precision.  */
 129   ctf_decl_prec_t cd_ordp;           /* Ordered precision.  */
 130   char *cd_buf;                      /* Buffer for output.  */
 131   int cd_err;                        /* Saved error value.  */
 132   int cd_enomem;                     /* Nonzero if OOM during printing.  */
 133 } ctf_decl_t;
 134
 135 typedef struct ctf_dmdef
 136 {
 137   ctf_list_t dmd_list;          /* List forward/back pointers.  */
 138   char *dmd_name;               /* Name of this member.  */
 139   ctf_id_t dmd_type;            /* Type of this member (for sou).  */
 140   unsigned long dmd_offset;     /* Offset of this member in bits (for sou).  */
 141   int dmd_value;                /* Value of this member (for enum).  */
 142 } ctf_dmdef_t;
 143
 144 typedef struct ctf_dtdef
 145 {
 146   ctf_list_t dtd_list;          /* List forward/back pointers.  */
 147   char *dtd_name;               /* Name associated with definition (if any).  */
 148   ctf_id_t dtd_type;            /* Type identifier for this definition.  */
 149   ctf_type_t dtd_data;          /* Type node (see <ctf.h>).  */
 150   union
 151   {
 152     ctf_list_t dtu_members;     /* struct, union, or enum */
 153     ctf_arinfo_t dtu_arr;       /* array */
 154     ctf_encoding_t dtu_enc;     /* integer or float */
 155     ctf_id_t *dtu_argv;         /* function */
 156     ctf_slice_t dtu_slice;      /* slice */
 157   } dtd_u;
 158 } ctf_dtdef_t;
 159
 160 typedef struct ctf_dvdef
 161 {
 162   ctf_list_t dvd_list;          /* List forward/back pointers.  */
 163   char *dvd_name;               /* Name associated with variable.  */
 164   ctf_id_t dvd_type;            /* Type of variable.  */
 165   unsigned long dvd_snapshots;  /* Snapshot count when inserted.  */
 166 } ctf_dvdef_t;
 167
 168 typedef struct ctf_bundle
 169 {
 170   ctf_file_t *ctb_file;         /* CTF container handle.  */
 171   ctf_id_t ctb_type;            /* CTF type identifier.  */
 172   ctf_dtdef_t *ctb_dtd;         /* CTF dynamic type definition (if any).  */
 173 } ctf_bundle_t;
 174
 175 /* The ctf_file is the structure used to represent a CTF container to library
 176    clients, who see it only as an opaque pointer.  Modifications can therefore
 177    be made freely to this structure without regard to client versioning.  The
 178    ctf_file_t typedef appears in <ctf-api.h> and declares a forward tag.
 179
 180    NOTE: ctf_update() requires that everything inside of ctf_file either be an
 181    immediate value, a pointer to dynamically allocated data *outside* of the
 182    ctf_file itself, or a pointer to statically allocated data.  If you add a
 183    pointer to ctf_file that points to something within the ctf_file itself,
 184    you must make corresponding changes to ctf_update().  */
 185
 186 struct ctf_file
 187 {
 188   const ctf_fileops_t *ctf_fileops; /* Version-specific file operations.  */
 189   ctf_sect_t ctf_data;              /* CTF data from object file.  */
 190   ctf_sect_t ctf_symtab;            /* Symbol table from object file.  */
 191   ctf_sect_t ctf_strtab;            /* String table from object file.  */
 192   void *ctf_data_mmapped;           /* CTF data we mmapped, to free later.  */
 193   size_t ctf_data_mmapped_len;      /* Length of CTF data we mmapped.  */
 194   ctf_hash_t *ctf_structs;          /* Hash table of struct types.  */
 195   ctf_hash_t *ctf_unions;           /* Hash table of union types.  */
 196   ctf_hash_t *ctf_enums;            /* Hash table of enum types.  */
 197   ctf_hash_t *ctf_names;            /* Hash table of remaining type names.  */
 198   ctf_lookup_t ctf_lookups[5];      /* Pointers to hashes for name lookup.  */
 199   ctf_strs_t ctf_str[2];            /* Array of string table base and bounds.  */
 200   const unsigned char *ctf_base;  /* Base of CTF header + uncompressed buffer.  */
 201   const unsigned char *ctf_buf;   /* Uncompressed CTF data buffer.  */
 202   size_t ctf_size;                /* Size of CTF header + uncompressed data.  */
 203   uint32_t *ctf_sxlate;           /* Translation table for symtab entries.  */
 204   unsigned long ctf_nsyms;        /* Number of entries in symtab xlate table.  */
 205   uint32_t *ctf_txlate;           /* Translation table for type IDs.  */
 206   uint32_t *ctf_ptrtab;           /* Translation table for pointer-to lookups.  */
 207   struct ctf_varent *ctf_vars;    /* Sorted variable->type mapping.  */
 208   unsigned long ctf_nvars;        /* Number of variables in ctf_vars.  */
 209   unsigned long ctf_typemax;      /* Maximum valid type ID number.  */
 210   const ctf_dmodel_t *ctf_dmodel; /* Data model pointer (see above).  */
 211   struct ctf_file *ctf_parent;    /* Parent CTF container (if any).  */
 212   const char *ctf_parlabel;       /* Label in parent container (if any).  */
 213   const char *ctf_parname;        /* Basename of parent (if any).  */
 214   char *ctf_dynparname;           /* Dynamically allocated name of parent.  */
 215   uint32_t ctf_parmax;            /* Highest type ID of a parent type.  */
 216   uint32_t ctf_refcnt;            /* Reference count (for parent links).  */
 217   uint32_t ctf_flags;             /* Libctf flags (see below).  */
 218   int ctf_errno;                  /* Error code for most recent error.  */
 219   int ctf_version;                /* CTF data version.  */
 220   ctf_dynhash_t *ctf_dthash;      /* Hash of dynamic type definitions.  */
 221   ctf_dynhash_t *ctf_dtbyname;    /* DTDs, indexed by name.  */
 222   ctf_list_t ctf_dtdefs;          /* List of dynamic type definitions.  */
 223   ctf_dynhash_t *ctf_dvhash;      /* Hash of dynamic variable mappings.  */
 224   ctf_list_t ctf_dvdefs;          /* List of dynamic variable definitions.  */
 225   size_t ctf_dtvstrlen;           /* Total length of dynamic type+var strings.  */
 226   unsigned long ctf_dtnextid;     /* Next dynamic type id to assign.  */
 227   unsigned long ctf_dtoldid;      /* Oldest id that has been committed.  */
 228   unsigned long ctf_snapshots;    /* ctf_snapshot() plus ctf_update() count.  */
 229   unsigned long ctf_snapshot_lu;  /* ctf_snapshot() call count at last update.  */
 230   ctf_archive_t *ctf_archive;     /* Archive this ctf_file_t came from.  */
 231   char *ctf_tmp_typeslice;        /* Storage for slicing up type names.  */
 232   size_t ctf_tmp_typeslicelen;    /* Size of the typeslice.  */
 233   void *ctf_specific;             /* Data for ctf_get/setspecific().  */
 234 };
 235
 236 /* An abstraction over both a ctf_file_t and a ctf_archive_t.  */
 237
 238 struct ctf_archive_internal
 239 {
 240   int ctfi_is_archive;
 241   ctf_file_t *ctfi_file;
 242   struct ctf_archive *ctfi_archive;
 243   ctf_sect_t ctfi_symsect;
 244   ctf_sect_t ctfi_strsect;
 245   void *ctfi_data;
 246   bfd *ctfi_abfd;                   /* Optional source of section data.  */
 247   void (*ctfi_bfd_close) (struct ctf_archive_internal *);
 248 };
 249
 250 /* Return x rounded up to an alignment boundary.
 251    eg, P2ROUNDUP(0x1234, 0x100) == 0x1300 (0x13*align)
 252    eg, P2ROUNDUP(0x5600, 0x100) == 0x5600 (0x56*align)  */
 253 #define P2ROUNDUP(x, align)             (-(-(x) & -(align)))
 254
 255 /* * If an offs is not aligned already then round it up and align it. */
 256 #define LCTF_ALIGN_OFFS(offs, align) ((offs + (align - 1)) & ~(align - 1))
 257
 258 #define LCTF_TYPE_ISPARENT(fp, id) ((id) <= fp->ctf_parmax)
 259 #define LCTF_TYPE_ISCHILD(fp, id) ((id) > fp->ctf_parmax)
 260 #define LCTF_TYPE_TO_INDEX(fp, id) ((id) & (fp->ctf_parmax))
 261 #define LCTF_INDEX_TO_TYPE(fp, id, child) (child ? ((id) | (fp->ctf_parmax+1)) : \
 262                                            (id))
 263
 264 #define LCTF_INDEX_TO_TYPEPTR(fp, i) \
 265   ((ctf_type_t *)((uintptr_t)(fp)->ctf_buf + (fp)->ctf_txlate[(i)]))
 266
 267 #define LCTF_INFO_KIND(fp, info)        ((fp)->ctf_fileops->ctfo_get_kind(info))
 268 #define LCTF_INFO_ISROOT(fp, info)      ((fp)->ctf_fileops->ctfo_get_root(info))
 269 #define LCTF_INFO_VLEN(fp, info)        ((fp)->ctf_fileops->ctfo_get_vlen(info))
 270 #define LCTF_VBYTES(fp, kind, size, vlen) \
 271   ((fp)->ctf_fileops->ctfo_get_vbytes(kind, size, vlen))
 272
 273 static inline ssize_t ctf_get_ctt_size (const ctf_file_t *fp,
 274                                         const ctf_type_t *tp,
 275                                         ssize_t *sizep,
 276                                         ssize_t *incrementp)
 277 {
 278   return (fp->ctf_fileops->ctfo_get_ctt_size (fp, tp, sizep, incrementp));
 279 }
 280
 281 #define LCTF_CHILD      0x0001  /* CTF container is a child */
 282 #define LCTF_RDWR       0x0002  /* CTF container is writable */
 283 #define LCTF_DIRTY      0x0004  /* CTF container has been modified */
 284
 285 extern const ctf_type_t *ctf_lookup_by_id (ctf_file_t **, ctf_id_t);
 286
 287 typedef unsigned int (*ctf_hash_fun) (const void *ptr);
 288 extern unsigned int ctf_hash_integer (const void *ptr);
 289 extern unsigned int ctf_hash_string (const void *ptr);
 290
 291 typedef int (*ctf_hash_eq_fun) (const void *, const void *);
 292 extern int ctf_hash_eq_integer (const void *, const void *);
 293 extern int ctf_hash_eq_string (const void *, const void *);
 294
 295 typedef void (*ctf_hash_free_fun) (void *);
 296
 297 extern ctf_hash_t *ctf_hash_create (unsigned long, ctf_hash_fun, ctf_hash_eq_fun);
 298 extern int ctf_hash_insert_type (ctf_hash_t *, ctf_file_t *, uint32_t, uint32_t);
 299 extern int ctf_hash_define_type (ctf_hash_t *, ctf_file_t *, uint32_t, uint32_t);
 300 extern ctf_id_t ctf_hash_lookup_type (ctf_hash_t *, ctf_file_t *, const char *);
 301 extern uint32_t ctf_hash_size (const ctf_hash_t *);
 302 extern void ctf_hash_destroy (ctf_hash_t *);
 303
 304 extern ctf_dynhash_t *ctf_dynhash_create (ctf_hash_fun, ctf_hash_eq_fun,
 305                                           ctf_hash_free_fun, ctf_hash_free_fun);
 306 extern int ctf_dynhash_insert (ctf_dynhash_t *, void *, void *);
 307 extern void ctf_dynhash_remove (ctf_dynhash_t *, const void *);
 308 extern void *ctf_dynhash_lookup (ctf_dynhash_t *, const void *);
 309 extern void ctf_dynhash_destroy (ctf_dynhash_t *);
 310
 311 #define ctf_list_prev(elem)     ((void *)(((ctf_list_t *)(elem))->l_prev))
 312 #define ctf_list_next(elem)     ((void *)(((ctf_list_t *)(elem))->l_next))
 313
 314 extern void ctf_list_append (ctf_list_t *, void *);
 315 extern void ctf_list_prepend (ctf_list_t *, void *);
 316 extern void ctf_list_delete (ctf_list_t *, void *);
 317
 318 extern void ctf_dtd_insert (ctf_file_t *, ctf_dtdef_t *);
 319 extern void ctf_dtd_delete (ctf_file_t *, ctf_dtdef_t *);
 320 extern ctf_dtdef_t *ctf_dtd_lookup (const ctf_file_t *, ctf_id_t);
 321 extern ctf_dtdef_t *ctf_dynamic_type (const ctf_file_t *, ctf_id_t);
 322
 323 extern void ctf_dvd_insert (ctf_file_t *, ctf_dvdef_t *);
 324 extern void ctf_dvd_delete (ctf_file_t *, ctf_dvdef_t *);
 325 extern ctf_dvdef_t *ctf_dvd_lookup (const ctf_file_t *, const char *);
 326
 327 extern const char *ctf_strraw (ctf_file_t *, uint32_t);
 328 extern const char *ctf_strptr (ctf_file_t *, uint32_t);
 329
 330 extern struct ctf_archive *ctf_arc_open_internal (const char *, int *);
 331 extern struct ctf_archive *ctf_arc_bufopen (const void *, size_t, int *);
 332 extern void ctf_arc_close_internal (struct ctf_archive *);
 333 extern void *ctf_set_open_errno (int *, int);
 334 extern long ctf_set_errno (ctf_file_t *, int);
 335
 336 _libctf_malloc_
 337 extern void *ctf_data_alloc (size_t);
 338 extern void ctf_data_free (void *, size_t);
 339 extern void ctf_data_protect (void *, size_t);
 340
 341 _libctf_malloc_
 342 extern void *ctf_mmap (size_t length, size_t offset, int fd);
 343 extern void ctf_munmap (void *, size_t);
 344 extern ssize_t ctf_pread (int fd, void *buf, ssize_t count, off_t offset);
 345
 346 _libctf_malloc_
 347 extern void *ctf_alloc (size_t);
 348 extern void ctf_free (void *);
 349
 350 _libctf_malloc_
 351 extern char *ctf_strdup (const char *);
 352 extern char *ctf_str_append (char *, const char *);
 353 extern const char *ctf_strerror (int);
 354
 355 extern ctf_id_t ctf_type_resolve_unsliced (ctf_file_t *, ctf_id_t);
 356 extern int ctf_type_kind_unsliced (ctf_file_t *, ctf_id_t);
 357
 358 _libctf_printflike_ (1, 2)
 359 extern void ctf_dprintf (const char *, ...);
 360 extern void libctf_init_debug (void);
 361
 362 extern Elf64_Sym *ctf_sym_to_elf64 (const Elf32_Sym *src, Elf64_Sym *dst);
 363
 364 /* Variables, all underscore-prepended. */
 365
 366 extern const char _CTF_SECTION[];       /* name of CTF ELF section */
 367 extern const char _CTF_NULLSTR[];       /* empty string */
 368
 369 extern int _libctf_debug;       /* debugging messages enabled */
 370
 371 #ifdef  __cplusplus
 372 }
 373 #endif
 374
 375 #endif /* _CTF_IMPL_H */