C++ wcstring::find方法代码示例

static size_t calc_prompt_lines(const wcstring &prompt) {
    // Hack for the common case where there's no newline at all. I don't know if a newline can
    // appear in an escape sequence, so if we detect a newline we have to defer to
    // calc_prompt_width_and_lines.
    size_t result = 1;
    if (prompt.find(L'\n') != wcstring::npos || prompt.find(L'\f') != wcstring::npos) {
        result = calc_prompt_layout(prompt, cached_layouts).line_count;
    }
    return result;
}

__attribute__((unused)) static void replace_all(wcstring &str, const wchar_t *needle,
                                                const wchar_t *replacement) {
    size_t needle_len = wcslen(needle);
    size_t offset = 0;
    while ((offset = str.find(needle, offset)) != wcstring::npos) {
        str.replace(offset, needle_len, replacement);
        offset += needle_len;
    }
}

int wildcard_expand_string(const wcstring &wc, const wcstring &base_dir, expand_flags_t flags, std::vector<completion_t> *output)
{
    assert(output != NULL);
    /* Hackish fix for 1631. We are about to call c_str(), which will produce a string truncated at any embedded nulls. We could fix this by passing around the size, etc. However embedded nulls are never allowed in a filename, so we just check for them and return 0 (no matches) if there is an embedded null. This isn't quite right, e.g. it will fail for \0?, but that is an edge case. */
    if (wc.find(L'\0') != wcstring::npos)
    {
        return 0;
    }
    return wildcard_expand(wc.c_str(), base_dir.c_str(), flags, output);
}

void tokenize_variable_array( const wcstring &val, std::vector<wcstring> &out)
{
    size_t pos = 0, end = val.size();
    while (pos < end) {
        size_t next_pos = val.find(ARRAY_SEP, pos);
        if (next_pos == wcstring::npos) break;
        out.push_back(val.substr(pos, next_pos - pos));
        pos = next_pos + 1; //skip the separator
    }
    out.push_back(val.substr(pos, end - pos));
}

int wildcard_expand_string(const wcstring &wc, const wcstring &base_dir, expand_flags_t flags, std::vector<completion_t> &outputs)
{
    /* Hackish fix for 1631. We are about to call c_str(), which will produce a string truncated at any embedded nulls. We could fix this by passing around the size, etc. However embedded nulls are never allowed in a filename, so we just check for them and return 0 (no matches) if there is an embedded null. This isn't quite right, e.g. it will fail for \0?, but that is an edge case. */
    if (wc.find(L'\0') != wcstring::npos)
    {
        return 0;
    }
    // PCA: not convinced this temporary variable is really necessary
    std::vector<completion_t> lst;
    int res = wildcard_expand(wc.c_str(), base_dir.c_str(), flags, lst);
    outputs.insert(outputs.end(), lst.begin(), lst.end());
    return res;
}

int wildcard_expand_string(const wcstring &wc, const wcstring &working_directory,
                           expand_flags_t flags, std::vector<completion_t> *output) {
    assert(output != NULL);
    // Fuzzy matching only if we're doing completions.
    assert(flags.get(expand_flag::for_completions) || !flags.get(expand_flag::fuzzy_match));

    // expand_flag::special_for_cd requires expand_flag::directories_only and
    // expand_flag::for_completions and expand_flag::no_descriptions.
    assert(!(flags.get(expand_flag::special_for_cd)) ||
           ((flags.get(expand_flag::directories_only)) &&
            (flags.get(expand_flag::for_completions)) &&
            (flags.get(expand_flag::no_descriptions))));

    // Hackish fix for issue #1631. We are about to call c_str(), which will produce a string
    // truncated at any embedded nulls. We could fix this by passing around the size, etc. However
    // embedded nulls are never allowed in a filename, so we just check for them and return 0 (no
    // matches) if there is an embedded null.
    if (wc.find(L'\0') != wcstring::npos) {
        return 0;
    }

    // Compute the prefix and base dir. The prefix is what we prepend for filesystem operations
    // (i.e. the working directory), the base_dir is the part of the wildcard consumed thus far,
    // which we also have to append. The difference is that the base_dir is returned as part of the
    // expansion, and the prefix is not.
    //
    // Check for a leading slash. If we find one, we have an absolute path: the prefix is empty, the
    // base dir is /, and the wildcard is the remainder. If we don't find one, the prefix is the
    // working directory, the base dir is empty.
    wcstring prefix = L"", base_dir = L"", effective_wc;
    if (string_prefixes_string(L"/", wc)) {
        base_dir = L"/";
        effective_wc = wc.substr(1);
    } else {
        prefix = working_directory;
        effective_wc = wc;
    }

    wildcard_expander_t expander(prefix, flags, output);
    expander.expand(base_dir, effective_wc.c_str(), base_dir);
    return expander.status_code();
}

/**
   The real implementation of wildcard expansion is in this
   function. Other functions are just wrappers around this one.

   This function traverses the relevant directory tree looking for
   matches, and recurses when needed to handle wildcrards spanning
   multiple components and recursive wildcards.

   Because this function calls itself recursively with substrings,
   it's important that the parameters be raw pointers instead of wcstring,
   which would be too expensive to construct for all substrings.
 */
static int wildcard_expand_internal(const wchar_t *wc,
                                    const wchar_t * const base_dir,
                                    expand_flags_t flags,
                                    std::vector<completion_t> *out,
                                    std::set<wcstring> &completion_set,
                                    std::set<file_id_t> &visited_files)
{
    /* Variables for traversing a directory */
    DIR *dir;

    /* The result returned */
    int res = 0;


    //  debug( 3, L"WILDCARD_EXPAND %ls in %ls", wc, base_dir );

    if (is_main_thread() ? reader_interrupted() : reader_thread_job_is_stale())
    {
        return -1;
    }

    if (!wc || !base_dir)
    {
        debug(2, L"Got null string on line %d of file %s", __LINE__, __FILE__);
        return 0;
    }

    const size_t base_dir_len = wcslen(base_dir);
    const size_t wc_len = wcslen(wc);

    if (flags & ACCEPT_INCOMPLETE)
    {
        /*
           Avoid excessive number of returned matches for wc ending with a *
        */
        if (wc_len > 0 && (wc[wc_len-1]==ANY_STRING))
        {
            wchar_t * foo = wcsdup(wc);
            foo[wc_len-1]=0;
            int res = wildcard_expand_internal(foo, base_dir, flags, out, completion_set, visited_files);
            free(foo);
            return res;
        }
    }

    /* Determine if we are the last segment */
    const wchar_t * const next_slash = wcschr(wc,L'/');
    const bool is_last_segment = (next_slash == NULL);
    const size_t wc_segment_len = next_slash ? next_slash - wc : wc_len;
    const wcstring wc_segment = wcstring(wc, wc_segment_len);
    
    /* Maybe this segment has no wildcards at all. If this is not the last segment, and it has no wildcards, then we don't need to match against the directory contents, and in fact we don't want to match since we may not be able to read it anyways (#2099). Don't even open the directory! */
    const bool segment_has_wildcards = wildcard_has(wc_segment, true /* internal, i.e. look for ANY_CHAR instead of ? */);
    if (! segment_has_wildcards && ! is_last_segment)
    {
        wcstring new_base_dir = make_path(base_dir, wc_segment);
        new_base_dir.push_back(L'/');
        
        /* Skip multiple separators */
        assert(next_slash != NULL);
        const wchar_t *new_wc = next_slash;
        while (*new_wc==L'/')
        {
            new_wc++;
        }
        /* Early out! */
        return wildcard_expand_internal(new_wc, new_base_dir.c_str(), flags, out, completion_set, visited_files);
    }
    
    /* Test for recursive match string in current segment */
    const bool is_recursive = (wc_segment.find(ANY_STRING_RECURSIVE) != wcstring::npos);
    

    const wchar_t *base_dir_or_cwd = (base_dir[0] == L'\0') ? L"." : base_dir;
    if (!(dir = wopendir(base_dir_or_cwd)))
    {
        return 0;
    }
    
    /*
      Is this segment of the wildcard the last?
    */
    if (is_last_segment)
    {
        /*
          Wildcard segment is the last segment,

          Insert all matching files/directories
//.........这里部分代码省略.........

void env_init(const struct config_paths_t *paths /* or NULL */)
{
    /*
      env_read_only variables can not be altered directly by the user
    */

    const wchar_t * const ro_keys[] =
    {
        L"status",
        L"history",
        L"version",
        L"_",
        L"LINES",
        L"COLUMNS",
        L"PWD",
        //L"SHLVL", // will be inserted a bit lower down
        L"FISH_VERSION",
    };
    for (size_t i=0; i < sizeof ro_keys / sizeof *ro_keys; i++)
    {
        env_read_only.insert(ro_keys[i]);
    }

    /*
       Names of all dynamically calculated variables
       */
    env_electric.insert(L"history");
    env_electric.insert(L"status");
    env_electric.insert(L"umask");
    env_electric.insert(L"COLUMNS");
    env_electric.insert(L"LINES");

    top = new env_node_t;
    global_env = top;
    global = &top->env;

    /*
      Now the environemnt variable handling is set up, the next step
      is to insert valid data
    */

    /*
      Import environment variables
    */
    for (char **p = (environ ? environ : __environ); p && *p; p++)
    {
        const wcstring key_and_val = str2wcstring(*p); //like foo=bar
        size_t eql = key_and_val.find(L'=');
        if (eql == wcstring::npos)
        {
            // no equals found
            if (is_read_only(key_and_val) || is_electric(key_and_val)) continue;
            env_set(key_and_val, L"", ENV_EXPORT | ENV_GLOBAL);
        }
        else
        {
            wcstring key = key_and_val.substr(0, eql);
            if (is_read_only(key) || is_electric(key)) continue;
            wcstring val = key_and_val.substr(eql + 1);
            if (variable_is_colon_delimited_array(key))
            {
                std::replace(val.begin(), val.end(), L':', ARRAY_SEP);
            }

            env_set(key, val.c_str(), ENV_EXPORT | ENV_GLOBAL);
        }
    }

    /* Set the given paths in the environment, if we have any */
    if (paths != NULL)
    {
        env_set(FISH_DATADIR_VAR, paths->data.c_str(), ENV_GLOBAL);
        env_set(FISH_SYSCONFDIR_VAR, paths->sysconf.c_str(), ENV_GLOBAL);
        env_set(FISH_HELPDIR_VAR, paths->doc.c_str(), ENV_GLOBAL);
        env_set(FISH_BIN_DIR, paths->bin.c_str(), ENV_GLOBAL);
    }

    /*
      Set up the PATH variable
    */
    setup_path();

    /*
      Set up the USER variable
    */
    if (env_get_string(L"USER").missing_or_empty())
    {
        const struct passwd *pw = getpwuid(getuid());
        if (pw && pw->pw_name)
        {
            const wcstring uname = str2wcstring(pw->pw_name);
            env_set(L"USER", uname.c_str(), ENV_GLOBAL | ENV_EXPORT);
        }
    }

    /*
      Set up the version variables
    */
    wcstring version = str2wcstring(get_fish_version());
    env_set(L"version", version.c_str(), ENV_GLOBAL);
//.........这里部分代码省略.........

void env_init(const struct config_paths_t *paths /* or NULL */)
{
    /*
      env_read_only variables can not be altered directly by the user
    */

    const wchar_t * const ro_keys[] =
    {
        L"status",
        L"history",
        L"version",
        L"_",
        L"LINES",
        L"COLUMNS",
        L"PWD",
        L"SHLVL",
        L"FISH_VERSION",
    };
    for (size_t i=0; i < sizeof ro_keys / sizeof *ro_keys; i++)
    {
        env_read_only.insert(ro_keys[i]);
    }

    /*
      HOME and USER should be writeable by root, since this can be a
      convenient way to install software.
    */
    if (getuid() != 0)
    {
        env_read_only.insert(L"HOME");
        env_read_only.insert(L"USER");
    }

    /*
       Names of all dynamically calculated variables
       */
    env_electric.insert(L"history");
    env_electric.insert(L"status");
    env_electric.insert(L"umask");

    top = new env_node_t;
    global_env = top;
    global = &top->env;

    /*
      Now the environemnt variable handling is set up, the next step
      is to insert valid data
    */

    /*
      Import environment variables
    */
    for (char **p = (environ ? environ : __environ); p && *p; p++)
    {
        const wcstring key_and_val = str2wcstring(*p); //like foo=bar
        size_t eql = key_and_val.find(L'=');
        if (eql == wcstring::npos)
        {
            // no equals found
            env_set(key_and_val, L"", ENV_EXPORT);
        }
        else
        {
            wcstring key = key_and_val.substr(0, eql);
            wcstring val = key_and_val.substr(eql + 1);
            if (variable_can_be_array(val))
            {
                std::replace(val.begin(), val.end(), L':', ARRAY_SEP);
            }

            env_set(key, val.c_str(), ENV_EXPORT | ENV_GLOBAL);
        }
    }

    /* Set the given paths in the environment, if we have any */
    if (paths != NULL)
    {
        env_set(FISH_DATADIR_VAR, paths->data.c_str(), ENV_GLOBAL | ENV_EXPORT);
        env_set(FISH_SYSCONFDIR_VAR, paths->sysconf.c_str(), ENV_GLOBAL | ENV_EXPORT);
        env_set(FISH_HELPDIR_VAR, paths->doc.c_str(), ENV_GLOBAL | ENV_EXPORT);
        env_set(FISH_BIN_DIR, paths->bin.c_str(), ENV_GLOBAL | ENV_EXPORT);
    }

    /*
      Set up the PATH variable
    */
    setup_path();

    /*
      Set up the USER variable
    */
    const struct passwd *pw = getpwuid(getuid());
    if (pw && pw->pw_name)
    {
        const wcstring uname = str2wcstring(pw->pw_name);
        env_set(L"USER", uname.c_str(), ENV_GLOBAL | ENV_EXPORT);
    }

    /*
      Set up the version variables
//.........这里部分代码省略.........

/// The real implementation of wildcard expansion is in this function. Other functions are just
/// wrappers around this one.
///
/// This function traverses the relevant directory tree looking for matches, and recurses when
/// needed to handle wildcrards spanning multiple components and recursive wildcards.
///
/// Because this function calls itself recursively with substrings, it's important that the
/// parameters be raw pointers instead of wcstring, which would be too expensive to construct for
/// all substrings.
///
/// Args:
/// base_dir: the "working directory" against which the wildcard is to be resolved
/// wc: the wildcard string itself, e.g. foo*bar/baz (where * is acutally ANY_CHAR)
/// prefix: the string that should be prepended for completions that replace their token.
//    This is usually the same thing as the original wildcard, but for fuzzy matching, we
//    expand intermediate segments. effective_prefix is always either empty, or ends with a slash
//    Note: this is only used when doing completions (EXPAND_FOR_COMPLETIONS is true), not
//    expansions
void wildcard_expander_t::expand(const wcstring &base_dir, const wchar_t *wc,
                                 const wcstring &effective_prefix) {
    assert(wc != NULL);

    if (interrupted()) {
        return;
    }

    // Get the current segment and compute interesting properties about it.
    const size_t wc_len = std::wcslen(wc);
    const wchar_t *const next_slash = std::wcschr(wc, L'/');
    const bool is_last_segment = (next_slash == NULL);
    const size_t wc_segment_len = next_slash ? next_slash - wc : wc_len;
    const wcstring wc_segment = wcstring(wc, wc_segment_len);
    const bool segment_has_wildcards =
        wildcard_has(wc_segment, true /* internal, i.e. look for ANY_CHAR instead of ? */);
    const wchar_t *const wc_remainder = next_slash ? next_slash + 1 : NULL;

    if (wc_segment.empty()) {
        // Handle empty segment.
        assert(!segment_has_wildcards);  //!OCLINT(multiple unary operator)
        if (is_last_segment) {
            this->expand_trailing_slash(base_dir, effective_prefix);
        } else {
            // Multiple adjacent slashes in the wildcard. Just skip them.
            this->expand(base_dir, wc_remainder, effective_prefix + L'/');
        }
    } else if (!segment_has_wildcards && !is_last_segment) {
        // Literal intermediate match. Note that we may not be able to actually read the directory
        // (issue #2099).
        assert(next_slash != NULL);

        // Absolute path of the intermediate directory
        const wcstring intermediate_dirpath = base_dir + wc_segment + L'/';

        // This just trumps everything.
        size_t before = this->resolved_completions->size();
        this->expand(intermediate_dirpath, wc_remainder, effective_prefix + wc_segment + L'/');

        // Maybe try a fuzzy match (#94) if nothing was found with the literal match. Respect
        // EXPAND_NO_DIRECTORY_ABBREVIATIONS (issue #2413).
        // Don't do fuzzy matches if the literal segment was valid (#3211)
        bool allow_fuzzy = (this->flags & (EXPAND_FUZZY_MATCH | EXPAND_NO_FUZZY_DIRECTORIES)) ==
                           EXPAND_FUZZY_MATCH;
        if (allow_fuzzy && this->resolved_completions->size() == before &&
            waccess(intermediate_dirpath, F_OK) != 0) {
            assert(this->flags & EXPAND_FOR_COMPLETIONS);
            DIR *base_dir_fd = open_dir(base_dir);
            if (base_dir_fd != NULL) {
                this->expand_literal_intermediate_segment_with_fuzz(
                    base_dir, base_dir_fd, wc_segment, wc_remainder, effective_prefix);
                closedir(base_dir_fd);
            }
        }
    } else {
        assert(!wc_segment.empty() && (segment_has_wildcards || is_last_segment));
        DIR *dir = open_dir(base_dir);
        if (dir) {
            if (is_last_segment) {
                // Last wildcard segment, nonempty wildcard.
                this->expand_last_segment(base_dir, dir, wc_segment, effective_prefix);
            } else {
                // Not the last segment, nonempty wildcard.
                assert(next_slash != NULL);
                this->expand_intermediate_segment(base_dir, dir, wc_segment, wc_remainder,
                                                  effective_prefix + wc_segment + L'/');
            }

            // Recursive wildcards require special handling.
            size_t asr_idx = wc_segment.find(ANY_STRING_RECURSIVE);
            if (asr_idx != wcstring::npos) {
                // Construct a "head + any" wildcard for matching stuff in this directory, and an
                // "any + tail" wildcard for matching stuff in subdirectories. Note that the
                // ANY_STRING_RECURSIVE character is present in both the head and the tail.
                const wcstring head_any(wc_segment, 0, asr_idx + 1);
                const wchar_t *any_tail = wc + asr_idx;
                assert(head_any.at(head_any.size() - 1) == ANY_STRING_RECURSIVE);
                assert(any_tail[0] == ANY_STRING_RECURSIVE);

                rewinddir(dir);
                this->expand_intermediate_segment(base_dir, dir, head_any, any_tail,
                                                  effective_prefix);
//.........这里部分代码省略.........

static bool path_get_path_core(const wcstring &cmd, wcstring *out_path,
                               const env_var_t &bin_path_var) {
    int err = ENOENT;
    debug(3, L"path_get_path( '%ls' )", cmd.c_str());

    // If the command has a slash, it must be a full path.
    if (cmd.find(L'/') != wcstring::npos) {
        if (waccess(cmd, X_OK) != 0) {
            return false;
        }

        struct stat buff;
        if (wstat(cmd, &buff)) {
            return false;
        }
        if (S_ISREG(buff.st_mode)) {
            if (out_path) out_path->assign(cmd);
            return true;
        }
        errno = EACCES;
        return false;
    }

    wcstring bin_path;
    if (!bin_path_var.missing()) {
        bin_path = bin_path_var;
    } else {
        if (contains(PREFIX L"/bin", L"/bin", L"/usr/bin")) {
            bin_path = L"/bin" ARRAY_SEP_STR L"/usr/bin";
        } else {
            bin_path = L"/bin" ARRAY_SEP_STR L"/usr/bin" ARRAY_SEP_STR PREFIX L"/bin";
        }
    }

    wcstring nxt_path;
    wcstokenizer tokenizer(bin_path, ARRAY_SEP_STR);
    while (tokenizer.next(nxt_path)) {
        if (nxt_path.empty()) continue;
        append_path_component(nxt_path, cmd);
        if (waccess(nxt_path, X_OK) == 0) {
            struct stat buff;
            if (wstat(nxt_path, &buff) == -1) {
                if (errno != EACCES) {
                    wperror(L"stat");
                }
                continue;
            }
            if (S_ISREG(buff.st_mode)) {
                if (out_path) out_path->swap(nxt_path);
                return true;
            }
            err = EACCES;
        } else {
            switch (errno) {
                case ENOENT:
                case ENAMETOOLONG:
                case EACCES:
                case ENOTDIR: {
                    break;
                }
                default: {
                    debug(1, MISSING_COMMAND_ERR_MSG, nxt_path.c_str());
                    wperror(L"access");
                }
            }
        }
    }

    errno = err;
    return false;
}

static bool path_get_path_core(const wcstring &cmd, wcstring *out_path,
                               const env_var_t &bin_path_var) {
    int err = ENOENT;
    debug(3, L"path_get_path( '%ls' )", cmd.c_str());

    // If the command has a slash, it must be a full path.
    if (cmd.find(L'/') != wcstring::npos) {
        if (waccess(cmd, X_OK) != 0) {
            return false;
        }

        struct stat buff;
        if (wstat(cmd, &buff)) {
            return false;
        }
        if (S_ISREG(buff.st_mode)) {
            if (out_path) out_path->assign(cmd);
            return true;
        }
        errno = EACCES;
        return false;
    }

    wcstring bin_path;
    if (!bin_path_var.missing()) {
        bin_path = bin_path_var;
    } else {
        // Note that PREFIX is defined in the `Makefile` and is thus defined when this module is
        // compiled. This ensures we always default to "/bin", "/usr/bin" and the bin dir defined
        // for the fish programs. Possibly with a duplicate dir if PREFIX is empty, "/", "/usr" or
        // "/usr/". If the PREFIX duplicates /bin or /usr/bin that is harmless other than a trivial
        // amount of time testing a path we've already tested.
        bin_path = L"/bin" ARRAY_SEP_STR L"/usr/bin" ARRAY_SEP_STR PREFIX L"/bin";
    }

    std::vector<wcstring> pathsv;
    tokenize_variable_array(bin_path, pathsv);
    for (auto next_path : pathsv) {
        if (next_path.empty()) continue;
        append_path_component(next_path, cmd);
        if (waccess(next_path, X_OK) == 0) {
            struct stat buff;
            if (wstat(next_path, &buff) == -1) {
                if (errno != EACCES) {
                    wperror(L"stat");
                }
                continue;
            }
            if (S_ISREG(buff.st_mode)) {
                if (out_path) *out_path = std::move(next_path);
                return true;
            }
            err = EACCES;
        } else {
            switch (errno) {
                case ENOENT:
                case ENAMETOOLONG:
                case EACCES:
                case ENOTDIR: {
                    break;
                }
                default: {
                    debug(1, MISSING_COMMAND_ERR_MSG, next_path.c_str());
                    wperror(L"access");
                    break;
                }
            }
        }
    }

    errno = err;
    return false;
}