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[got-portable.git] / include / got_error.h

/*
 * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
 * Copyright (c) 2020 Ori Bernstein <ori@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "got_compat.h"

/* Error codes */
#define GOT_ERR_OK              0
#define GOT_ERR_ERRNO           1
#define GOT_ERR_NOT_GIT_REPO    2
#define GOT_ERR_BAD_FILETYPE    3
#define GOT_ERR_BAD_PATH        4
#define GOT_ERR_NOT_REF         5
#define GOT_ERR_IO              6
#define GOT_ERR_EOF             7
#define GOT_ERR_DECOMPRESSION   8
#define GOT_ERR_NO_SPACE        9
#define GOT_ERR_BAD_OBJ_HDR     10
#define GOT_ERR_OBJ_TYPE        11
#define GOT_ERR_BAD_OBJ_DATA    12
#define GOT_ERR_AMBIGUOUS_ID    13
#define GOT_ERR_BAD_PACKIDX     14
#define GOT_ERR_PACKIDX_CSUM    15
#define GOT_ERR_BAD_PACKFILE    16
#define GOT_ERR_NO_OBJ          17
#define GOT_ERR_NOT_IMPL        18
#define GOT_ERR_OBJ_NOT_PACKED  19
#define GOT_ERR_BAD_DELTA_CHAIN 20
#define GOT_ERR_BAD_DELTA       21
#define GOT_ERR_COMPRESSION     22
#define GOT_ERR_BAD_OBJ_ID_STR  23
#define GOT_ERR_WORKTREE_EXISTS 26
#define GOT_ERR_WORKTREE_META   27
#define GOT_ERR_WORKTREE_VERS   28
#define GOT_ERR_WORKTREE_BUSY   29
#define GOT_ERR_DIR_OBSTRUCTED  30
#define GOT_ERR_FILE_OBSTRUCTED 31
#define GOT_ERR_RECURSION       32
#define GOT_ERR_TIMEOUT         33
#define GOT_ERR_INTERRUPT       34
#define GOT_ERR_PRIVSEP_READ    35
#define GOT_ERR_PRIVSEP_LEN     36
#define GOT_ERR_PRIVSEP_PIPE    37
#define GOT_ERR_PRIVSEP_NO_FD   38
#define GOT_ERR_PRIVSEP_MSG     39
#define GOT_ERR_PRIVSEP_DIED    40
#define GOT_ERR_PRIVSEP_EXIT    41
#define GOT_ERR_PACK_OFFSET     42
#define GOT_ERR_OBJ_EXISTS      43
#define GOT_ERR_BAD_OBJ_ID      44
#define GOT_ERR_ITER_BUSY       45
#define GOT_ERR_ITER_COMPLETED  46
#define GOT_ERR_RANGE           47
#define GOT_ERR_EXPECTED        48 /* for use in regress tests only */
#define GOT_ERR_CANCELLED       49
#define GOT_ERR_NO_TREE_ENTRY   50
#define GOT_ERR_FILEIDX_SIG     51
#define GOT_ERR_FILEIDX_VER     52
#define GOT_ERR_FILEIDX_CSUM    53
#define GOT_ERR_PATH_PREFIX     54
#define GOT_ERR_ANCESTRY        55
#define GOT_ERR_FILEIDX_BAD     56
#define GOT_ERR_BAD_REF_DATA    57
#define GOT_ERR_TREE_DUP_ENTRY  58
#define GOT_ERR_DIR_DUP_ENTRY   59
#define GOT_ERR_NOT_WORKTREE    60
#define GOT_ERR_UUID_VERSION    61
#define GOT_ERR_UUID_INVALID    62
#define GOT_ERR_UUID            63
#define GOT_ERR_LOCKFILE_TIMEOUT 64
#define GOT_ERR_BAD_REF_NAME    65
#define GOT_ERR_WORKTREE_REPO   66
#define GOT_ERR_FILE_MODIFIED   67
#define GOT_ERR_FILE_STATUS     68
#define GOT_ERR_COMMIT_CONFLICT 69
#define GOT_ERR_BAD_REF_TYPE    70
#define GOT_ERR_COMMIT_NO_AUTHOR 71
#define GOT_ERR_COMMIT_HEAD_CHANGED 72
#define GOT_ERR_COMMIT_OUT_OF_DATE 73
#define GOT_ERR_COMMIT_MSG_EMPTY 74
#define GOT_ERR_DIR_NOT_EMPTY   75
#define GOT_ERR_COMMIT_NO_CHANGES 76
#define GOT_ERR_BRANCH_MOVED    77
#define GOT_ERR_OBJ_TOO_LARGE   78
#define GOT_ERR_SAME_BRANCH     79
#define GOT_ERR_ROOT_COMMIT     80
#define GOT_ERR_MIXED_COMMITS   81
#define GOT_ERR_CONFLICTS       82
#define GOT_ERR_BRANCH_EXISTS   83
#define GOT_ERR_MODIFIED        84
#define GOT_ERR_NOT_REBASING    85
#define GOT_ERR_EMPTY_REBASE    86
#define GOT_ERR_REBASE_COMMITID 87
#define GOT_ERR_REBASING        88
#define GOT_ERR_REBASE_PATH     89
#define GOT_ERR_NOT_HISTEDIT    90
#define GOT_ERR_EMPTY_HISTEDIT  91
#define GOT_ERR_NO_HISTEDIT_CMD 92
#define GOT_ERR_HISTEDIT_SYNTAX 93
#define GOT_ERR_HISTEDIT_CANCEL 94
/* 95 is currently unused */
#define GOT_ERR_HISTEDIT_BUSY   96
#define GOT_ERR_HISTEDIT_CMD    97
#define GOT_ERR_HISTEDIT_PATH   98
/* 99 is currently unused */
#define GOT_ERR_COMMIT_BRANCH   100
#define GOT_ERR_FILE_STAGED     101
#define GOT_ERR_STAGE_NO_CHANGE 102
#define GOT_ERR_STAGE_CONFLICT  103
#define GOT_ERR_STAGE_OUT_OF_DATE 104
#define GOT_ERR_FILE_NOT_STAGED 105
#define GOT_ERR_STAGED_PATHS    106
#define GOT_ERR_PATCH_CHOICE    107
#define GOT_ERR_COMMIT_NO_EMAIL 108
#define GOT_ERR_TAG_EXISTS      109
#define GOT_ERR_GIT_REPO_FORMAT 110
#define GOT_ERR_REBASE_REQUIRED 111
#define GOT_ERR_REGEX           112
#define GOT_ERR_REF_NAME_MINUS  113
#define GOT_ERR_GITCONFIG_SYNTAX 114
#define GOT_ERR_REBASE_OUT_OF_DATE 115
#define GOT_ERR_CACHE_DUP_ENTRY 116
#define GOT_ERR_QUERYSTRING     117
#define GOT_ERR_FETCH_FAILED    118
#define GOT_ERR_PARSE_URI       119
#define GOT_ERR_BAD_PROTO       120
#define GOT_ERR_ADDRINFO        121
#define GOT_ERR_BAD_PACKET      122
#define GOT_ERR_NO_REMOTE       123
#define GOT_ERR_FETCH_NO_BRANCH 124
#define GOT_ERR_FETCH_BAD_REF   125
#define GOT_ERR_TREE_ENTRY_TYPE 126
#define GOT_ERR_PARSE_CONFIG    127
#define GOT_ERR_NO_CONFIG_FILE  128
#define GOT_ERR_BAD_SYMLINK     129
#define GOT_ERR_GIT_REPO_EXT    130
#define GOT_ERR_CANNOT_PACK     131
#define GOT_ERR_LONELY_PACKIDX  132
#define GOT_ERR_OBJ_CSUM        133
#define GOT_ERR_SEND_BAD_REF    134
#define GOT_ERR_SEND_FAILED     135
#define GOT_ERR_SEND_EMPTY      136
#define GOT_ERR_SEND_ANCESTRY   137
#define GOT_ERR_CAPA_DELETE_REFS 138
#define GOT_ERR_SEND_DELETE_REF 139
#define GOT_ERR_SEND_TAG_EXISTS 140
#define GOT_ERR_NOT_MERGING     141
#define GOT_ERR_MERGE_OUT_OF_DATE 142
#define GOT_ERR_MERGE_STAGED_PATHS 143
#define GOT_ERR_MERGE_COMMIT_OUT_OF_DATE 143
#define GOT_ERR_MERGE_BUSY      144
#define GOT_ERR_MERGE_PATH      145

static const struct got_error {
        int code;
        const char *msg;
} got_errors[] = {
        { GOT_ERR_OK,           "no error occured?!?" },
        { GOT_ERR_ERRNO,        "see errno" },
        { GOT_ERR_NOT_GIT_REPO, "no git repository found" },
        { GOT_ERR_BAD_FILETYPE, "bad file type" },
        { GOT_ERR_BAD_PATH,     "bad path" },
        { GOT_ERR_NOT_REF,      "no such reference found" },
        { GOT_ERR_IO,           "input/output error" },
        { GOT_ERR_EOF,          "unexpected end of file" },
        { GOT_ERR_DECOMPRESSION,"decompression failed" },
        { GOT_ERR_NO_SPACE,     "buffer too small" },
        { GOT_ERR_BAD_OBJ_HDR,  "bad object header" },
        { GOT_ERR_OBJ_TYPE,     "wrong type of object" },
        { GOT_ERR_BAD_OBJ_DATA, "bad object data" },
        { GOT_ERR_AMBIGUOUS_ID, "ambiguous object ID" },
        { GOT_ERR_BAD_PACKIDX,  "bad pack index file" },
        { GOT_ERR_PACKIDX_CSUM, "pack index file checksum error" },
        { GOT_ERR_BAD_PACKFILE, "bad pack file" },
        { GOT_ERR_NO_OBJ,       "object not found" },
        { GOT_ERR_NOT_IMPL,     "feature not implemented" },
        { GOT_ERR_OBJ_NOT_PACKED,"object is not packed" },
        { GOT_ERR_BAD_DELTA_CHAIN,"bad delta chain" },
        { GOT_ERR_BAD_DELTA,    "bad delta" },
        { GOT_ERR_COMPRESSION,  "compression failed" },
        { GOT_ERR_BAD_OBJ_ID_STR,"bad object id string" },
        { GOT_ERR_WORKTREE_EXISTS,"worktree already exists" },
        { GOT_ERR_WORKTREE_META,"bad worktree meta data" },
        { GOT_ERR_WORKTREE_VERS,"unsupported worktree format version" },
        { GOT_ERR_WORKTREE_BUSY,"worktree already locked" },
        { GOT_ERR_FILE_OBSTRUCTED,"file is obstructed" },
        { GOT_ERR_RECURSION,    "recursion limit reached" },
        { GOT_ERR_TIMEOUT,      "operation timed out" },
        { GOT_ERR_INTERRUPT,    "operation interrupted" },
        { GOT_ERR_PRIVSEP_READ, "no data received in imsg" },
        { GOT_ERR_PRIVSEP_LEN,  "unexpected amount of data received in imsg" },
        { GOT_ERR_PRIVSEP_PIPE, "privsep peer process closed pipe" },
        { GOT_ERR_PRIVSEP_NO_FD,"privsep file descriptor unavailable" },
        { GOT_ERR_PRIVSEP_MSG,  "received unexpected privsep message" },
        { GOT_ERR_PRIVSEP_DIED, "unprivileged process died unexpectedly" },
        { GOT_ERR_PRIVSEP_EXIT, "bad exit code from unprivileged process" },
        { GOT_ERR_PACK_OFFSET,  "bad offset in pack file" },
        { GOT_ERR_OBJ_EXISTS,   "object already exists" },
        { GOT_ERR_BAD_OBJ_ID,   "bad object id" },
        { GOT_ERR_ITER_BUSY,    "iteration already in progress" },
        { GOT_ERR_ITER_COMPLETED,"iteration completed" },
        { GOT_ERR_RANGE,        "value out of range" },
        { GOT_ERR_EXPECTED,     "expected an error but have no error" },
        { GOT_ERR_CANCELLED,    "operation in progress has been cancelled" },
        { GOT_ERR_NO_TREE_ENTRY,"no such entry found in tree" },
        { GOT_ERR_FILEIDX_SIG,  "bad file index signature" },
        { GOT_ERR_FILEIDX_VER,  "unknown file index format version" },
        { GOT_ERR_FILEIDX_CSUM, "bad file index checksum" },
        { GOT_ERR_PATH_PREFIX,  "worktree already contains items from a "
                                "different path prefix" },
        { GOT_ERR_ANCESTRY,     "target commit is on a different branch" },
        { GOT_ERR_FILEIDX_BAD,  "file index is corrupt" },
        { GOT_ERR_BAD_REF_DATA, "could not parse reference data" },
        { GOT_ERR_TREE_DUP_ENTRY,"duplicate entry in tree object" },
        { GOT_ERR_DIR_DUP_ENTRY,"duplicate entry in directory" },
        { GOT_ERR_NOT_WORKTREE, "no got work tree found" },
        { GOT_ERR_UUID_VERSION, "bad uuid version" },
        { GOT_ERR_UUID_INVALID, "uuid invalid" },
        { GOT_ERR_UUID,         "uuid error" },
        { GOT_ERR_LOCKFILE_TIMEOUT,"lockfile timeout" },
        { GOT_ERR_BAD_REF_NAME, "bad reference name" },
        { GOT_ERR_WORKTREE_REPO,"cannot create worktree inside a git repository" },
        { GOT_ERR_FILE_MODIFIED,"file contains modifications" },
        { GOT_ERR_FILE_STATUS,  "file has unexpected status" },
        { GOT_ERR_COMMIT_CONFLICT,"cannot commit file in conflicted status" },
        { GOT_ERR_BAD_REF_TYPE, "bad reference type" },
        { GOT_ERR_COMMIT_NO_AUTHOR,"GOT_AUTHOR environment variable is not set" },
        { GOT_ERR_COMMIT_HEAD_CHANGED, "branch head in repository has changed "
            "while commit was in progress" },
        { GOT_ERR_COMMIT_OUT_OF_DATE, "work tree must be updated before these "
            "changes can be committed" },
        { GOT_ERR_COMMIT_MSG_EMPTY, "commit message cannot be empty" },
        { GOT_ERR_DIR_NOT_EMPTY, "directory exists and is not empty" },
        { GOT_ERR_COMMIT_NO_CHANGES, "no changes to commit" },
        { GOT_ERR_BRANCH_MOVED, "work tree's head reference now points to a "
            "different branch; new head reference and/or update -b required" },
        { GOT_ERR_OBJ_TOO_LARGE,        "object too large" },
        { GOT_ERR_SAME_BRANCH,  "commit is already contained in this branch" },
        { GOT_ERR_ROOT_COMMIT,  "specified commit has no parent commit" },
        { GOT_ERR_MIXED_COMMITS,"work tree contains files from multiple "
            "base commits; the entire work tree must be updated first" },
        { GOT_ERR_CONFLICTS,    "work tree contains conflicted files; these "
            "conflicts must be resolved first" },
        { GOT_ERR_BRANCH_EXISTS,"specified branch already exists" },
        { GOT_ERR_MODIFIED,     "work tree contains local changes; these "
            "changes must be committed or reverted first" },
        { GOT_ERR_NOT_REBASING, "rebase operation not in progress" },
        { GOT_ERR_EMPTY_REBASE, "no commits to rebase" },
        { GOT_ERR_REBASE_COMMITID,"rebase commit ID mismatch" },
        { GOT_ERR_REBASING,     "a rebase operation is in progress in this "
            "work tree and must be continued or aborted first" },
        { GOT_ERR_REBASE_PATH,  "cannot rebase branch which contains "
            "changes outside of this work tree's path prefix" },
        { GOT_ERR_NOT_HISTEDIT, "histedit operation not in progress" },
        { GOT_ERR_EMPTY_HISTEDIT,"no commits to edit; perhaps the work tree "
            "must be updated to an older commit first" },
        { GOT_ERR_NO_HISTEDIT_CMD,"no histedit commands provided" },
        { GOT_ERR_HISTEDIT_SYNTAX,"syntax error in histedit command list" },
        { GOT_ERR_HISTEDIT_CANCEL,"histedit operation cancelled" },
        { 95, "unused error code" },
        { GOT_ERR_HISTEDIT_BUSY,"histedit operation is in progress in this "
            "work tree and must be continued or aborted first" },
        { GOT_ERR_HISTEDIT_CMD, "bad histedit command" },
        { GOT_ERR_HISTEDIT_PATH, "cannot edit branch history which contains "
            "changes outside of this work tree's path prefix" },
        { 99, "unused error code" },
        { GOT_ERR_COMMIT_BRANCH, "will not commit to a branch outside the "
            "\"refs/heads/\" reference namespace" },
        { GOT_ERR_FILE_STAGED, "file is staged" },
        { GOT_ERR_STAGE_NO_CHANGE, "no changes to stage" },
        { GOT_ERR_STAGE_CONFLICT, "cannot stage file in conflicted status" },
        { GOT_ERR_STAGE_OUT_OF_DATE, "work tree must be updated before "
            "changes can be staged" },
        { GOT_ERR_FILE_NOT_STAGED, "file is not staged" },
        { GOT_ERR_STAGED_PATHS, "work tree contains files with staged "
            "changes; these changes must be committed or unstaged first" },
        { GOT_ERR_PATCH_CHOICE, "invalid patch choice" },
        { GOT_ERR_COMMIT_NO_EMAIL,"GOT_AUTHOR environment variable contains "
            "no email address; an email address is required for compatibility "
            "with Git" },
        { GOT_ERR_TAG_EXISTS,"specified tag already exists" },
        { GOT_ERR_GIT_REPO_FORMAT,"unknown git repository format version" },
        { GOT_ERR_REBASE_REQUIRED,"specified branch must be rebased first" },
        { GOT_ERR_REGEX, "regular expression error" },
        { GOT_ERR_REF_NAME_MINUS, "reference name may not start with '-'" },
        { GOT_ERR_GITCONFIG_SYNTAX, "gitconfig syntax error" },
        { GOT_ERR_REBASE_OUT_OF_DATE, "work tree must be updated before it "
            "can be used to rebase a branch" },
        { GOT_ERR_CACHE_DUP_ENTRY, "duplicate cache entry" },
        { GOT_ERR_QUERYSTRING, "bad querystring" },
        { GOT_ERR_FETCH_FAILED, "fetch failed" },
        { GOT_ERR_PARSE_URI, "failed to parse uri" },
        { GOT_ERR_BAD_PROTO, "unknown protocol" },
        { GOT_ERR_ADDRINFO, "getaddrinfo failed" },
        { GOT_ERR_BAD_PACKET, "bad packet received" },
        { GOT_ERR_NO_REMOTE, "remote repository not found" },
        { GOT_ERR_FETCH_NO_BRANCH, "could not find any branches to fetch" },
        { GOT_ERR_FETCH_BAD_REF, "reference cannot be fetched" },
        { GOT_ERR_TREE_ENTRY_TYPE, "unexpected tree entry type" },
        { GOT_ERR_PARSE_CONFIG, "configuration file syntax error" },
        { GOT_ERR_NO_CONFIG_FILE, "configuration file doesn't exit" },
        { GOT_ERR_BAD_SYMLINK, "symbolic link points outside of paths under "
            "version control" },
        { GOT_ERR_GIT_REPO_EXT, "unsupported repository format extension" },
        { GOT_ERR_CANNOT_PACK, "not enough objects to pack" },
        { GOT_ERR_LONELY_PACKIDX, "pack index has no corresponding pack file; "
            "pack file must be restored or 'gotadmin cleanup -p' must be run" },
        { GOT_ERR_OBJ_CSUM, "bad object checksum" },
        { GOT_ERR_SEND_BAD_REF, "reference cannot be sent" },
        { GOT_ERR_SEND_FAILED, "could not send pack file" },
        { GOT_ERR_SEND_EMPTY, "no references to send" },
        { GOT_ERR_SEND_ANCESTRY, "fetch and rebase required" },
        { GOT_ERR_CAPA_DELETE_REFS, "server cannot delete references" },
        { GOT_ERR_SEND_DELETE_REF, "reference cannot be deleted" },
        { GOT_ERR_SEND_TAG_EXISTS, "tag already exists on server" },
        { GOT_ERR_NOT_MERGING,  "merge operation not in progress" },
        { GOT_ERR_MERGE_OUT_OF_DATE, "work tree must be updated before it "
            "can be used to merge a branch" },
        { GOT_ERR_MERGE_STAGED_PATHS, "work tree contains files with staged "
            "changes; these changes must be unstaged before merging can "
            "proceed" },
        { GOT_ERR_MERGE_COMMIT_OUT_OF_DATE, "merging cannot proceed because "
            "the work tree is no longer up-to-date; merge must be aborted "
            "and retried" },
        { GOT_ERR_MERGE_BUSY,"a merge operation is in progress in this "
            "work tree and must be continued or aborted first" },
        { GOT_ERR_MERGE_PATH,   "cannot merge branch which contains "
            "changes outside of this work tree's path prefix" },
};

/*
 * Get an error object from the above list, for a given error code.
 * The error message is fixed.
 */
const struct got_error *got_error(int);

/*
 * Get an error object from the above list, for a given error code.
 * Use the specified error message instead of the default one.
 * Caution: If the message buffer lives in dynamically allocated memory,
 * then this memory likely won't be freed.
 */
const struct got_error *got_error_msg(int, const char *);

/*
 * Get a statically allocated error object with code GOT_ERR_ERRNO
 * and an error message obtained from strerror(3), prefixed with a
 * string.
 */
const struct got_error *got_error_from_errno(const char *);

/*
 * Get a statically allocated error object with code GOT_ERR_ERRNO
 * and an error message obtained from strerror(3), prefixed with two
 * strings.
 */
const struct got_error *got_error_from_errno2(const char *, const char *);

/*
 * Get a statically allocated error object with code GOT_ERR_ERRNO
 * and an error message obtained from strerror(3), prefixed with three
 * strings.
 */
const struct got_error *got_error_from_errno3(const char *, const char *,
    const char *);

/*
 * Get a statically allocated error object with code GOT_ERR_ERRNO
 * and an error message obtained from strerror(3), prefixed with a
 * string built with vsnprintf(3) from the provided format string
 * and the variable-length list of additional arguments.
 */
const struct got_error *got_error_from_errno_fmt(const char *, ...);

/*
 * Set errno to the specified error code and return a statically
 * allocated error object with code GOT_ERR_ERRNO and an error
 * message obtained from strerror(3), optionally prefixed with a
 * string.
 */
const struct got_error *got_error_set_errno(int, const char *);

/*
 * If ferror(3) indicates an error status for the FILE, obtain an error
 * from got_error_from_errno(). Else, obtain the error via got_error()
 * with the error code provided in the second argument.
 */
const struct got_error *got_ferror(FILE *, int);

/*
 * Obtain an error with code GOT_ERR_NO_OBJ and an error message which
 * contains the specified object ID. The message buffer is statically
 * allocated; future invocations of this function will overwrite the
 * message set during earlier invocations.
 */
struct got_object_id; /* forward declaration */
const struct got_error *got_error_no_obj(struct got_object_id *);

/*
 * Obtain an error with code GOT_ERR_NOT_REF and an error message which
 * contains the specified reference name. The message buffer is statically
 * allocated; future invocations of this function will overwrite the
 * message set during earlier invocations.
 */
const struct got_error *got_error_not_ref(const char *);

/* Return an error based on a uuid(3) status code. */
const struct got_error *got_error_uuid(uint32_t, const char *);

/* Return an error with a path prefixed to the error message. */
const struct got_error *got_error_path(const char *, int);

/*
 * Return an error with an error message prefix built by vsnprintf(3)
 * from the provided format string and the variable-length list of
 * additional arguments.
*/
const struct got_error *got_error_fmt(int, const char *, ...);

/*
 * Check whether open(2) with O_NOFOLLOW failed on a symlink.
 * This must be called directly after open(2) because it uses errno!
 */
int got_err_open_nofollow_on_symlink(void);