| 1 | /* Miscellaneous utilities. |
| 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 | #include <ctf-impl.h> |
| 21 | #include <string.h> |
| 22 | |
| 23 | /* Simple doubly-linked list append routine. This implementation assumes that |
| 24 | each list element contains an embedded ctf_list_t as the first member. |
| 25 | An additional ctf_list_t is used to store the head (l_next) and tail |
| 26 | (l_prev) pointers. The current head and tail list elements have their |
| 27 | previous and next pointers set to NULL, respectively. */ |
| 28 | |
| 29 | void |
| 30 | ctf_list_append (ctf_list_t *lp, void *newp) |
| 31 | { |
| 32 | ctf_list_t *p = lp->l_prev; /* p = tail list element. */ |
| 33 | ctf_list_t *q = newp; /* q = new list element. */ |
| 34 | |
| 35 | lp->l_prev = q; |
| 36 | q->l_prev = p; |
| 37 | q->l_next = NULL; |
| 38 | |
| 39 | if (p != NULL) |
| 40 | p->l_next = q; |
| 41 | else |
| 42 | lp->l_next = q; |
| 43 | } |
| 44 | |
| 45 | /* Prepend the specified existing element to the given ctf_list_t. The |
| 46 | existing pointer should be pointing at a struct with embedded ctf_list_t. */ |
| 47 | |
| 48 | void |
| 49 | ctf_list_prepend (ctf_list_t * lp, void *newp) |
| 50 | { |
| 51 | ctf_list_t *p = newp; /* p = new list element. */ |
| 52 | ctf_list_t *q = lp->l_next; /* q = head list element. */ |
| 53 | |
| 54 | lp->l_next = p; |
| 55 | p->l_prev = NULL; |
| 56 | p->l_next = q; |
| 57 | |
| 58 | if (q != NULL) |
| 59 | q->l_prev = p; |
| 60 | else |
| 61 | lp->l_prev = p; |
| 62 | } |
| 63 | |
| 64 | /* Delete the specified existing element from the given ctf_list_t. The |
| 65 | existing pointer should be pointing at a struct with embedded ctf_list_t. */ |
| 66 | |
| 67 | void |
| 68 | ctf_list_delete (ctf_list_t *lp, void *existing) |
| 69 | { |
| 70 | ctf_list_t *p = existing; |
| 71 | |
| 72 | if (p->l_prev != NULL) |
| 73 | p->l_prev->l_next = p->l_next; |
| 74 | else |
| 75 | lp->l_next = p->l_next; |
| 76 | |
| 77 | if (p->l_next != NULL) |
| 78 | p->l_next->l_prev = p->l_prev; |
| 79 | else |
| 80 | lp->l_prev = p->l_prev; |
| 81 | } |
| 82 | |
| 83 | /* Return 1 if the list is empty. */ |
| 84 | |
| 85 | int |
| 86 | ctf_list_empty_p (ctf_list_t *lp) |
| 87 | { |
| 88 | return (lp->l_next == NULL && lp->l_prev == NULL); |
| 89 | } |
| 90 | |
| 91 | /* Convert a 32-bit ELF symbol into Elf64 and return a pointer to it. */ |
| 92 | |
| 93 | Elf64_Sym * |
| 94 | ctf_sym_to_elf64 (const Elf32_Sym *src, Elf64_Sym *dst) |
| 95 | { |
| 96 | dst->st_name = src->st_name; |
| 97 | dst->st_value = src->st_value; |
| 98 | dst->st_size = src->st_size; |
| 99 | dst->st_info = src->st_info; |
| 100 | dst->st_other = src->st_other; |
| 101 | dst->st_shndx = src->st_shndx; |
| 102 | |
| 103 | return dst; |
| 104 | } |
| 105 | |
| 106 | /* A string appender working on dynamic strings. Returns NULL on OOM. */ |
| 107 | |
| 108 | char * |
| 109 | ctf_str_append (char *s, const char *append) |
| 110 | { |
| 111 | size_t s_len = 0; |
| 112 | |
| 113 | if (append == NULL) |
| 114 | return s; |
| 115 | |
| 116 | if (s != NULL) |
| 117 | s_len = strlen (s); |
| 118 | |
| 119 | size_t append_len = strlen (append); |
| 120 | |
| 121 | if ((s = realloc (s, s_len + append_len + 1)) == NULL) |
| 122 | return NULL; |
| 123 | |
| 124 | memcpy (s + s_len, append, append_len); |
| 125 | s[s_len + append_len] = '\0'; |
| 126 | |
| 127 | return s; |
| 128 | } |
| 129 | |
| 130 | /* A version of ctf_str_append that returns the old string on OOM. */ |
| 131 | |
| 132 | char * |
| 133 | ctf_str_append_noerr (char *s, const char *append) |
| 134 | { |
| 135 | char *new_s; |
| 136 | |
| 137 | new_s = ctf_str_append (s, append); |
| 138 | if (!new_s) |
| 139 | return s; |
| 140 | return new_s; |
| 141 | } |
| 142 | |
| 143 | /* A realloc() that fails noisily if called with any ctf_str_num_users. */ |
| 144 | void * |
| 145 | ctf_realloc (ctf_file_t *fp, void *ptr, size_t size) |
| 146 | { |
| 147 | if (fp->ctf_str_num_refs > 0) |
| 148 | { |
| 149 | ctf_dprintf ("%p: attempt to realloc() string table with %lu active refs\n", |
| 150 | (void *) fp, (unsigned long) fp->ctf_str_num_refs); |
| 151 | return NULL; |
| 152 | } |
| 153 | return realloc (ptr, size); |
| 154 | } |
| 155 | |
| 156 | /* Store the specified error code into errp if it is non-NULL, and then |
| 157 | return NULL for the benefit of the caller. */ |
| 158 | |
| 159 | void * |
| 160 | ctf_set_open_errno (int *errp, int error) |
| 161 | { |
| 162 | if (errp != NULL) |
| 163 | *errp = error; |
| 164 | return NULL; |
| 165 | } |
| 166 | |
| 167 | /* Store the specified error code into the CTF container, and then return |
| 168 | CTF_ERR / -1 for the benefit of the caller. */ |
| 169 | |
| 170 | unsigned long |
| 171 | ctf_set_errno (ctf_file_t * fp, int err) |
| 172 | { |
| 173 | fp->ctf_errno = err; |
| 174 | return CTF_ERR; |
| 175 | } |