lib/error.c

   1 /*
   2  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <sys/queue.h>
  18
  19 #include <errno.h>
  20 #include <limits.h>
  21 #include <stdarg.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <zlib.h>
  26
  27 #include "got_compat.h"
  28
  29 #include "got_error.h"
  30 #include "got_object.h"
  31
  32 #include "got_lib_delta.h"
  33 #include "got_lib_inflate.h"
  34 #include "got_lib_object.h"
  35 #include "got_lib_hash.h"
  36 #include "got_lib_object_parse.h"
  37
  38 #ifndef nitems
  39 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
  40 #endif
  41
  42 #if defined(__GLIBC__)
  43         /*
  44          * The autoconf test for strerror_r is broken in current versions
  45          * of autoconf: https://savannah.gnu.org/support/?110367
  46          */
  47 char *__xpg_strerror_r(int, char *, size_t);
  48 #define strerror_r __xpg_strerror_r
  49 #endif
  50
  51 static const struct got_error got_errors[] = {
  52         { GOT_ERR_OK,           "no error occured?!?" },
  53         { GOT_ERR_ERRNO,        "see errno" },
  54         { GOT_ERR_NOT_GIT_REPO, "no git repository found" },
  55         { GOT_ERR_BAD_FILETYPE, "bad file type" },
  56         { GOT_ERR_BAD_PATH,     "bad path" },
  57         { GOT_ERR_NOT_REF,      "no such reference found" },
  58         { GOT_ERR_IO,           "input/output error" },
  59         { GOT_ERR_EOF,          "unexpected end of file" },
  60         { GOT_ERR_DECOMPRESSION,"decompression failed" },
  61         { GOT_ERR_NO_SPACE,     "buffer too small" },
  62         { GOT_ERR_BAD_OBJ_HDR,  "bad object header" },
  63         { GOT_ERR_OBJ_TYPE,     "wrong type of object" },
  64         { GOT_ERR_BAD_OBJ_DATA, "bad object data" },
  65         { GOT_ERR_AMBIGUOUS_ID, "ambiguous object ID" },
  66         { GOT_ERR_BAD_PACKIDX,  "bad pack index file" },
  67         { GOT_ERR_PACKIDX_CSUM, "pack index file checksum error" },
  68         { GOT_ERR_BAD_PACKFILE, "bad pack file" },
  69         { GOT_ERR_NO_OBJ,       "object not found" },
  70         { GOT_ERR_NOT_IMPL,     "feature not implemented" },
  71         { GOT_ERR_OBJ_NOT_PACKED,"object is not packed" },
  72         { GOT_ERR_BAD_DELTA_CHAIN,"bad delta chain" },
  73         { GOT_ERR_BAD_DELTA,    "bad delta" },
  74         { GOT_ERR_COMPRESSION,  "compression failed" },
  75         { GOT_ERR_BAD_OBJ_ID_STR,"bad object id string" },
  76         { GOT_ERR_WORKTREE_EXISTS,"worktree already exists" },
  77         { GOT_ERR_WORKTREE_META,"bad worktree meta data" },
  78         { GOT_ERR_WORKTREE_VERS,"unsupported worktree format version" },
  79         { GOT_ERR_WORKTREE_BUSY,"worktree already locked" },
  80         { GOT_ERR_FILE_OBSTRUCTED,"file is obstructed" },
  81         { GOT_ERR_RECURSION,    "recursion limit reached" },
  82         { GOT_ERR_TIMEOUT,      "operation timed out" },
  83         { GOT_ERR_INTERRUPT,    "operation interrupted" },
  84         { GOT_ERR_PRIVSEP_READ, "no data received in imsg" },
  85         { GOT_ERR_PRIVSEP_LEN,  "unexpected amount of data received in imsg" },
  86         { GOT_ERR_PRIVSEP_PIPE, "privsep peer process closed pipe" },
  87         { GOT_ERR_PRIVSEP_NO_FD,"privsep file descriptor unavailable" },
  88         { GOT_ERR_PRIVSEP_MSG,  "received unexpected privsep message" },
  89         { GOT_ERR_PRIVSEP_DIED, "unprivileged process died unexpectedly" },
  90         { GOT_ERR_PRIVSEP_EXIT, "bad exit code from unprivileged process" },
  91         { GOT_ERR_PACK_OFFSET,  "bad offset in pack file" },
  92         { GOT_ERR_OBJ_EXISTS,   "object already exists" },
  93         { GOT_ERR_BAD_OBJ_ID,   "bad object id" },
  94         { GOT_ERR_ITER_BUSY,    "iteration already in progress" },
  95         { GOT_ERR_ITER_COMPLETED,"iteration completed" },
  96         { GOT_ERR_RANGE,        "value out of range" },
  97         { GOT_ERR_EXPECTED,     "expected an error but have no error" },
  98         { GOT_ERR_CANCELLED,    "operation in progress has been cancelled" },
  99         { GOT_ERR_NO_TREE_ENTRY,"no such entry found in tree" },
 100         { GOT_ERR_FILEIDX_SIG,  "bad file index signature" },
 101         { GOT_ERR_FILEIDX_VER,  "unknown file index format version" },
 102         { GOT_ERR_FILEIDX_CSUM, "bad file index checksum" },
 103         { GOT_ERR_PATH_PREFIX,  "worktree already contains items from a "
 104                                 "different path prefix" },
 105         { GOT_ERR_ANCESTRY,     "target commit is on a different branch" },
 106         { GOT_ERR_FILEIDX_BAD,  "file index is corrupt" },
 107         { GOT_ERR_BAD_REF_DATA, "could not parse reference data" },
 108         { GOT_ERR_TREE_DUP_ENTRY,"duplicate entry in tree object" },
 109         { GOT_ERR_DIR_DUP_ENTRY,"duplicate entry in directory" },
 110         { GOT_ERR_NOT_WORKTREE, "no work tree found" },
 111         { GOT_ERR_UUID_VERSION, "bad uuid version" },
 112         { GOT_ERR_UUID_INVALID, "uuid invalid" },
 113         { GOT_ERR_UUID,         "uuid error" },
 114         { GOT_ERR_LOCKFILE_TIMEOUT,"lockfile timeout" },
 115         { GOT_ERR_BAD_REF_NAME, "bad reference name" },
 116         { GOT_ERR_WORKTREE_REPO,"cannot create worktree inside a git repository" },
 117         { GOT_ERR_FILE_MODIFIED,"file contains modifications" },
 118         { GOT_ERR_FILE_STATUS,  "file has unexpected status" },
 119         { GOT_ERR_COMMIT_CONFLICT,"cannot commit file in conflicted status" },
 120         { GOT_ERR_BAD_REF_TYPE, "bad reference type" },
 121         { GOT_ERR_COMMIT_NO_AUTHOR,"GOT_AUTHOR environment variable is not set" },
 122         { GOT_ERR_COMMIT_HEAD_CHANGED, "branch head in repository has changed "
 123             "while commit was in progress" },
 124         { GOT_ERR_COMMIT_OUT_OF_DATE, "work tree must be updated before these "
 125             "changes can be committed" },
 126         { GOT_ERR_COMMIT_MSG_EMPTY, "commit message cannot be empty" },
 127         { GOT_ERR_DIR_NOT_EMPTY, "directory exists and is not empty" },
 128         { GOT_ERR_COMMIT_NO_CHANGES, "no changes to commit" },
 129         { GOT_ERR_BRANCH_MOVED, "work tree's head reference now points to a "
 130             "different branch; new head reference and/or update -b required" },
 131         { GOT_ERR_OBJ_TOO_LARGE,        "object too large" },
 132         { GOT_ERR_SAME_BRANCH,  "commit is already contained in this branch" },
 133         { GOT_ERR_ROOT_COMMIT,  "specified commit has no parent commit" },
 134         { GOT_ERR_MIXED_COMMITS,"work tree contains files from multiple "
 135             "base commits; the entire work tree must be updated first" },
 136         { GOT_ERR_CONFLICTS,    "work tree contains conflicted files; these "
 137             "conflicts must be resolved first" },
 138         { GOT_ERR_BRANCH_EXISTS,"specified branch already exists" },
 139         { GOT_ERR_MODIFIED,     "work tree contains local changes; these "
 140             "changes must be committed or reverted first" },
 141         { GOT_ERR_NOT_REBASING, "rebase operation not in progress" },
 142         { GOT_ERR_REBASE_COMMITID,"rebase commit ID mismatch" },
 143         { GOT_ERR_REBASING,     "a rebase operation is in progress in this "
 144             "work tree and must be continued or aborted first" },
 145         { GOT_ERR_REBASE_PATH,  "cannot rebase branch which contains "
 146             "changes outside of this work tree's path prefix" },
 147         { GOT_ERR_NOT_HISTEDIT, "histedit operation not in progress" },
 148         { GOT_ERR_EMPTY_HISTEDIT,"no commits to edit; perhaps the work tree "
 149             "must be updated to an older commit first" },
 150         { GOT_ERR_NO_HISTEDIT_CMD,"no histedit commands provided" },
 151         { GOT_ERR_HISTEDIT_SYNTAX,"syntax error in histedit command list" },
 152         { GOT_ERR_HISTEDIT_CANCEL,"histedit operation cancelled" },
 153         { 95, "unused error code" },
 154         { GOT_ERR_HISTEDIT_BUSY,"histedit operation is in progress in this "
 155             "work tree and must be continued or aborted first" },
 156         { GOT_ERR_HISTEDIT_CMD, "bad histedit command" },
 157         { GOT_ERR_HISTEDIT_PATH, "cannot edit branch history which contains "
 158             "changes outside of this work tree's path prefix" },
 159         { GOT_ERR_PACKFILE_CSUM, "pack file checksum error" },
 160         { GOT_ERR_COMMIT_BRANCH, "will not commit to a branch outside the "
 161             "\"refs/heads/\" reference namespace" },
 162         { GOT_ERR_FILE_STAGED, "file is staged" },
 163         { GOT_ERR_STAGE_NO_CHANGE, "no changes to stage" },
 164         { GOT_ERR_STAGE_CONFLICT, "cannot stage file in conflicted status" },
 165         { GOT_ERR_STAGE_OUT_OF_DATE, "work tree must be updated before "
 166             "changes can be staged" },
 167         { GOT_ERR_FILE_NOT_STAGED, "file is not staged" },
 168         { GOT_ERR_STAGED_PATHS, "work tree contains files with staged "
 169             "changes; these changes must be committed or unstaged first" },
 170         { GOT_ERR_PATCH_CHOICE, "invalid patch choice" },
 171         { GOT_ERR_COMMIT_NO_EMAIL, "commit author's email address is required "
 172             "for compatibility with Git" },
 173         { GOT_ERR_TAG_EXISTS,"specified tag already exists" },
 174         { GOT_ERR_GIT_REPO_FORMAT,"unknown git repository format version" },
 175         { GOT_ERR_REBASE_REQUIRED,"specified branch must be rebased first" },
 176         { GOT_ERR_REGEX, "regular expression error" },
 177         { GOT_ERR_REF_NAME_MINUS, "reference name may not start with '-'" },
 178         { GOT_ERR_GITCONFIG_SYNTAX, "gitconfig syntax error" },
 179         { GOT_ERR_REBASE_OUT_OF_DATE, "work tree must be updated before it "
 180             "can be used to rebase a branch" },
 181         { GOT_ERR_CACHE_DUP_ENTRY, "duplicate cache entry" },
 182         { GOT_ERR_FETCH_FAILED, "fetch failed" },
 183         { GOT_ERR_PARSE_URI, "failed to parse uri" },
 184         { GOT_ERR_BAD_PROTO, "unknown protocol" },
 185         { GOT_ERR_ADDRINFO, "getaddrinfo failed" },
 186         { GOT_ERR_BAD_PACKET, "bad packet received" },
 187         { GOT_ERR_NO_REMOTE, "remote repository not found" },
 188         { GOT_ERR_FETCH_NO_BRANCH, "could not find any branches to fetch" },
 189         { GOT_ERR_FETCH_BAD_REF, "reference cannot be fetched" },
 190         { GOT_ERR_TREE_ENTRY_TYPE, "unexpected tree entry type" },
 191         { GOT_ERR_PARSE_CONFIG, "configuration file syntax error" },
 192         { GOT_ERR_NO_CONFIG_FILE, "configuration file doesn't exit" },
 193         { GOT_ERR_BAD_SYMLINK, "symbolic link points outside of paths under "
 194             "version control" },
 195         { GOT_ERR_GIT_REPO_EXT, "unsupported repository format extension" },
 196         { GOT_ERR_CANNOT_PACK, "not enough objects to pack" },
 197         { GOT_ERR_LONELY_PACKIDX, "pack index has no corresponding pack file; "
 198             "pack file must be restored or 'gotadmin cleanup -p' must be run" },
 199         { GOT_ERR_OBJ_CSUM, "bad object checksum" },
 200         { GOT_ERR_SEND_BAD_REF, "reference cannot be sent" },
 201         { GOT_ERR_SEND_FAILED, "could not send pack file" },
 202         { GOT_ERR_SEND_EMPTY, "no references to send" },
 203         { GOT_ERR_SEND_ANCESTRY, "fetch and rebase required" },
 204         { GOT_ERR_CAPA_DELETE_REFS, "server cannot delete references" },
 205         { GOT_ERR_SEND_DELETE_REF, "reference cannot be deleted" },
 206         { GOT_ERR_SEND_TAG_EXISTS, "tag already exists on server" },
 207         { GOT_ERR_NOT_MERGING,  "merge operation not in progress" },
 208         { GOT_ERR_MERGE_OUT_OF_DATE, "work tree must be updated before it "
 209             "can be used to merge a branch" },
 210         { GOT_ERR_MERGE_STAGED_PATHS, "work tree contains files with staged "
 211             "changes; these changes must be unstaged before merging can "
 212             "proceed" },
 213         { GOT_ERR_MERGE_BUSY,"a merge operation is in progress in this "
 214             "work tree and must be continued or aborted first" },
 215         { GOT_ERR_MERGE_PATH,   "cannot merge branch which contains "
 216             "changes outside of this work tree's path prefix" },
 217         { GOT_ERR_FILE_BINARY, "found a binary file instead of text" },
 218         { GOT_ERR_PATCH_MALFORMED, "malformed patch" },
 219         { GOT_ERR_PATCH_TRUNCATED, "patch truncated" },
 220         { GOT_ERR_NO_PATCH, "no patch found" },
 221         { GOT_ERR_HUNK_FAILED, "hunk failed to apply" },
 222         { GOT_ERR_PATCH_FAILED, "patch failed to apply" },
 223         { GOT_ERR_FILEIDX_DUP_ENTRY, "duplicate file index entry" },
 224         { GOT_ERR_PIN_PACK, "could not pin pack file" },
 225         { GOT_ERR_BAD_TAG_SIGNATURE, "invalid tag signature" },
 226         { GOT_ERR_VERIFY_TAG_SIGNATURE, "cannot verify signature" },
 227         { GOT_ERR_SIGNING_TAG, "unable to sign tag" },
 228         { GOT_ERR_BAD_OPTION, "option cannot be used" },
 229         { GOT_ERR_BAD_QUERYSTRING, "invalid query string" },
 230         { GOT_ERR_INTEGRATE_BRANCH, "will not integrate into a reference "
 231             "outside the \"refs/heads/\" reference namespace" },
 232         { GOT_ERR_BAD_REQUEST, "unexpected request received" },
 233         { GOT_ERR_CLIENT_ID, "unknown client identifier" },
 234         { GOT_ERR_REPO_TEMPFILE, "no repository tempfile available" },
 235         { GOT_ERR_REFS_PROTECTED, "reference namespace is protected" },
 236         { GOT_ERR_REF_PROTECTED, "reference is protected" },
 237         { GOT_ERR_REF_BUSY, "reference cannot be updated; please try again" },
 238         { GOT_ERR_COMMIT_BAD_AUTHOR, "commit author formatting would "
 239             "make Git unhappy" },
 240         { GOT_ERR_UID, "bad user ID" },
 241         { GOT_ERR_GID, "bad group ID" },
 242         { GOT_ERR_NO_PROG, "command not found or not accessible" },
 243         { GOT_ERR_MERGE_COMMIT_OUT_OF_DATE, "merging cannot proceed because "
 244             "the work tree is no longer up-to-date; merge must be aborted "
 245             "and retried" },
 246         { GOT_ERR_BUNDLE_FORMAT, "unknown git bundle version" },
 247         { GOT_ERR_BAD_KEYWORD, "invalid commit keyword" }
 248 };
 249
 250 static struct got_custom_error {
 251         struct got_error err;
 252         char msg[GOT_ERR_MAX_MSG_SIZE];
 253 } custom_errors[16];
 254
 255 static struct got_custom_error *
 256 get_custom_err(void)
 257 {
 258         static unsigned int idx;
 259         return &custom_errors[(idx++) % nitems(custom_errors)];
 260 }
 261
 262 const struct got_error *
 263 got_error(int code)
 264 {
 265         size_t i;
 266
 267         for (i = 0; i < nitems(got_errors); i++) {
 268                 if (code == got_errors[i].code)
 269                         return &got_errors[i];
 270         }
 271
 272         abort();
 273 }
 274
 275 const struct got_error *
 276 got_error_msg(int code, const char *msg)
 277 {
 278         struct got_custom_error *cerr = get_custom_err();
 279         struct got_error *err = &cerr->err;
 280         size_t i;
 281
 282         for (i = 0; i < nitems(got_errors); i++) {
 283                 if (code == got_errors[i].code) {
 284                         err->code = code;
 285                         strlcpy(cerr->msg, msg, sizeof(cerr->msg));
 286                         err->msg = cerr->msg;
 287                         return err;
 288                 }
 289         }
 290
 291         abort();
 292 }
 293
 294 const struct got_error *
 295 got_error_from_errno(const char *prefix)
 296 {
 297         struct got_custom_error *cerr = get_custom_err();
 298         struct got_error *err = &cerr->err;
 299         char strerr[128];
 300
 301         strerror_r(errno, strerr, sizeof(strerr));
 302         snprintf(cerr->msg, sizeof(cerr->msg), "%s: %s", prefix, strerr);
 303
 304         err->code = GOT_ERR_ERRNO;
 305         err->msg = cerr->msg;
 306         return err;
 307 }
 308
 309 const struct got_error *
 310 got_error_from_errno2(const char *prefix, const char *prefix2)
 311 {
 312         struct got_custom_error *cerr = get_custom_err();
 313         struct got_error *err = &cerr->err;
 314         char strerr[128];
 315
 316         strerror_r(errno, strerr, sizeof(strerr));
 317         snprintf(cerr->msg, sizeof(cerr->msg), "%s: %s: %s", prefix, prefix2,
 318             strerr);
 319
 320         err->code = GOT_ERR_ERRNO;
 321         err->msg = cerr->msg;
 322         return err;
 323 }
 324
 325 const struct got_error *
 326 got_error_from_errno3(const char *prefix, const char *prefix2,
 327     const char *prefix3)
 328 {
 329         struct got_custom_error *cerr = get_custom_err();
 330         struct got_error *err = &cerr->err;
 331         char strerr[128];
 332
 333         strerror_r(errno, strerr, sizeof(strerr));
 334         snprintf(cerr->msg, sizeof(cerr->msg), "%s: %s: %s: %s", prefix,
 335             prefix2, prefix3, strerr);
 336
 337         err->code = GOT_ERR_ERRNO;
 338         err->msg = cerr->msg;
 339         return err;
 340 }
 341
 342 const struct got_error *
 343 got_error_from_errno_fmt(const char *fmt, ...)
 344 {
 345         struct got_custom_error *cerr = get_custom_err();
 346         struct got_error *err = &cerr->err;
 347         char buf[PATH_MAX * 4];
 348         char strerr[128];
 349         va_list ap;
 350
 351         va_start(ap, fmt);
 352         vsnprintf(buf, sizeof(buf), fmt, ap);
 353         va_end(ap);
 354
 355         strerror_r(errno, strerr, sizeof(strerr));
 356         snprintf(cerr->msg, sizeof(cerr->msg), "%s: %s", buf, strerr);
 357
 358         err->code = GOT_ERR_ERRNO;
 359         err->msg = cerr->msg;
 360         return err;
 361 }
 362
 363 const struct got_error *
 364 got_error_set_errno(int code, const char *prefix)
 365 {
 366         errno = code;
 367         return got_error_from_errno(prefix);
 368 }
 369
 370 const struct got_error *
 371 got_ferror(FILE *f, int code)
 372 {
 373         if (ferror(f))
 374                 return got_error_from_errno("");
 375         return got_error(code);
 376 }
 377
 378 const struct got_error *
 379 got_error_no_obj(struct got_object_id *id)
 380 {
 381         char id_str[GOT_OBJECT_ID_HEX_MAXLEN];
 382         char msg[sizeof("object   not found") + sizeof(id_str)];
 383         int ret;
 384
 385         if (!got_object_id_hex(id, id_str, sizeof(id_str)))
 386                 return got_error(GOT_ERR_NO_OBJ);
 387
 388         ret = snprintf(msg, sizeof(msg), "object %s not found", id_str);
 389         if (ret < 0 || (size_t)ret >= sizeof(msg))
 390                 return got_error(GOT_ERR_NO_OBJ);
 391
 392         return got_error_msg(GOT_ERR_NO_OBJ, msg);
 393 }
 394
 395 const struct got_error *
 396 got_error_checksum(struct got_object_id *id)
 397 {
 398         char id_str[GOT_OBJECT_ID_HEX_MAXLEN];
 399         char msg[sizeof("checksum failure for object ") + sizeof(id_str)];
 400         int ret;
 401
 402         if (!got_object_id_hex(id, id_str, sizeof(id_str)))
 403                 return got_error(GOT_ERR_OBJ_CSUM);
 404
 405         ret = snprintf(msg, sizeof(msg), "checksum failure for object %s",
 406             id_str);
 407         if (ret < 0 || (size_t)ret >= sizeof(msg))
 408                 return got_error(GOT_ERR_OBJ_CSUM);
 409
 410         return got_error_msg(GOT_ERR_OBJ_CSUM, msg);
 411 }
 412
 413 const struct got_error *
 414 got_error_not_ref(const char *refname)
 415 {
 416         char msg[sizeof("reference   not found") + 1004];
 417         int ret;
 418
 419         ret = snprintf(msg, sizeof(msg), "reference %s not found", refname);
 420         if (ret < 0 || (size_t)ret >= sizeof(msg))
 421                 return got_error(GOT_ERR_NOT_REF);
 422
 423         return got_error_msg(GOT_ERR_NOT_REF, msg);
 424 }
 425
 426 const struct got_error *
 427 got_error_uuid(uint32_t uuid_status, const char *prefix)
 428 {
 429         switch (uuid_status) {
 430         case uuid_s_ok:
 431                 return NULL;
 432         case uuid_s_bad_version:
 433                 return got_error(GOT_ERR_UUID_VERSION);
 434         case uuid_s_invalid_string_uuid:
 435                 return got_error(GOT_ERR_UUID_INVALID);
 436         case uuid_s_no_memory:
 437                 return got_error_set_errno(ENOMEM, prefix);
 438         default:
 439                 return got_error(GOT_ERR_UUID);
 440         }
 441 }
 442
 443 const struct got_error *
 444 got_error_path(const char *path, int code)
 445 {
 446         struct got_custom_error *cerr = get_custom_err();
 447         struct got_error *err = &cerr->err;
 448         size_t i;
 449
 450         for (i = 0; i < nitems(got_errors); i++) {
 451                 if (code == got_errors[i].code) {
 452                         err->code = code;
 453                         snprintf(cerr->msg, sizeof(cerr->msg), "%s: %s", path,
 454                             got_errors[i].msg);
 455                         err->msg = cerr->msg;
 456                         return err;
 457                 }
 458         }
 459
 460         abort();
 461 }
 462
 463 const struct got_error *
 464 got_error_fmt(int code, const char *fmt, ...)
 465 {
 466         struct got_custom_error *cerr = get_custom_err();
 467         struct got_error *err = &cerr->err;
 468         char buf[PATH_MAX * 4];
 469         va_list ap;
 470         size_t i;
 471
 472         va_start(ap, fmt);
 473         vsnprintf(buf, sizeof(buf), fmt, ap);
 474         va_end(ap);
 475
 476         for (i = 0; i < nitems(got_errors); i++) {
 477                 if (code == got_errors[i].code) {
 478                         err->code = code;
 479                         snprintf(cerr->msg, sizeof(cerr->msg), "%s: %s", buf,
 480                             got_errors[i].msg);
 481                         err->msg = cerr->msg;
 482                         return err;
 483                 }
 484         }
 485
 486         abort();
 487 }
 488
 489 int
 490 got_err_open_nofollow_on_symlink(void)
 491 {
 492         /*
 493          * Check whether open(2) with O_NOFOLLOW failed on a symlink.
 494          * Posix mandates ELOOP and OpenBSD follows it. Others return
 495          * different error codes. We carry this workaround to help the
 496          * portable version a little.
 497          */
 498         return (errno == ELOOP
 499 #ifdef EMLINK
 500         || errno == EMLINK
 501 #endif
 502 #ifdef EFTYPE
 503         || errno == EFTYPE
 504 #endif
 505         );
 506 }