Handle stat() errors, slight refactor

Symlink target information is now stored in entries.
This commit is contained in:
Přemysl Eric Janouch 2018-10-25 14:51:19 +02:00
parent 6aa1e5d8a5
commit 3e40137f7a
Signed by: p
GPG Key ID: A0420B94F92B9493
1 changed files with 63 additions and 65 deletions

128
sdn.cpp
View File

@ -119,7 +119,8 @@ fun decode_type (mode_t m) -> wchar_t {
if (S_ISDIR (m)) return L'd'; if (S_ISBLK (m)) return L'b';
if (S_ISCHR (m)) return L'c'; if (S_ISLNK (m)) return L'l';
if (S_ISFIFO (m)) return L'p'; if (S_ISSOCK (m)) return L's';
return L'-';
if (S_ISREG (m)) return L'-';
return L'?';
}
/// Return the modes of a file in the usual stat/ls format
@ -265,15 +266,13 @@ fun decode_attrs (const vector<string> &attrs) -> chtype {
#define CTRL 31 &
struct row {
struct entry {
string filename, target_path;
struct stat info = {}, target_info = {};
enum { MODES, USER, GROUP, SIZE, MTIME, FILENAME, COLUMNS };
ncstring cols[COLUMNS];
};
struct entry {
// TODO: how to present symlink target, stat of the target?
// unique_ptr<string> target; struct stat target_info;
string filename; struct stat info; struct row row;
auto operator< (const entry &other) -> bool {
auto a = S_ISDIR (info.st_mode);
auto b = S_ISDIR (other.info.st_mode);
@ -302,7 +301,7 @@ static struct {
vector<entry> entries; ///< Current directory entries
int offset, cursor; ///< Scroll offset and cursor position
bool full_view; ///< Show extended information
int max_widths[row::COLUMNS]; ///< Column widths
int max_widths[entry::COLUMNS]; ///< Column widths
string chosen; ///< Chosen item for the command line
bool chosen_full; ///< Use the full path
@ -331,7 +330,6 @@ fun ls_format (const string &filename, const struct stat &info) -> chtype {
int type = LS_ORPHAN;
auto set = [&](int t) { if (g.ls_colors.count (t)) type = t; };
// TODO: LS_MISSING if available and this is a missing symlink target
// TODO: go by readdir() information when stat() isn't available yet
if (S_ISREG (info.st_mode)) {
type = LS_FILE;
if (info.st_nlink > 1)
@ -381,22 +379,51 @@ fun ls_format (const string &filename, const struct stat &info) -> chtype {
return format;
}
// XXX: this will probably have to be changed to make_entry and run lstat itself
fun make_row (const string &filename, const struct stat &info) -> row {
row r;
fun make_entry (const struct dirent *f) -> entry {
entry e;
e.filename = f->d_name;
e.info.st_mode = DTTOIF (f->d_type);
auto& info = e.info;
// TODO: benchmark just readdir() vs. lstat(), also on dead mounts;
// it might make sense to stat asynchronously in threads
// http://lkml.iu.edu/hypermail//linux/kernel/0804.3/1616.html
if (lstat (f->d_name, &info)) {
e.cols[entry::MODES] = apply_attrs ({ decode_type (info.st_mode),
L'?', L'?', L'?', L'?', L'?', L'?', L'?', L'?', L'?' }, 0);
e.cols[entry::USER] = e.cols[entry::GROUP] =
e.cols[entry::SIZE] = e.cols[entry::MTIME] = apply_attrs (L"?", 0);
auto format = ls_format (e.filename, info);
e.cols[entry::FILENAME] = apply_attrs (to_wide (e.filename), format);
return e;
}
if (S_ISLNK (info.st_mode)) {
char buf[PATH_MAX] = {};
auto len = readlink (f->d_name, buf, sizeof buf);
if (len < 0 || size_t (len) >= sizeof buf) {
e.target_path = "?";
} else {
e.target_path = buf;
(void) lstat (buf, &e.target_info);
}
}
auto mode = decode_mode (info.st_mode);
// This is a Linux-only extension
if (acl_extended_file_nofollow (filename.c_str ()) > 0)
if (acl_extended_file_nofollow (f->d_name) > 0)
mode += L"+";
r.cols[row::MODES] = apply_attrs (mode, 0);
e.cols[entry::MODES] = apply_attrs (mode, 0);
auto usr = g.unames.find (info.st_uid);
r.cols[row::USER] = (usr != g.unames.end ())
e.cols[entry::USER] = (usr != g.unames.end ())
? apply_attrs (to_wide (usr->second), 0)
: apply_attrs (to_wstring (info.st_uid), 0);
auto grp = g.gnames.find (info.st_gid);
r.cols[row::GROUP] = (grp != g.unames.end ())
e.cols[entry::GROUP] = (grp != g.unames.end ())
? apply_attrs (to_wide (grp->second), 0)
: apply_attrs (to_wstring (info.st_gid), 0);
@ -405,25 +432,29 @@ fun make_row (const string &filename, const struct stat &info) -> row {
else if (info.st_size >> 30) size = to_wstring (info.st_size >> 30) + L"G";
else if (info.st_size >> 20) size = to_wstring (info.st_size >> 20) + L"M";
else if (info.st_size >> 10) size = to_wstring (info.st_size >> 10) + L"K";
r.cols[row::SIZE] = apply_attrs (size, 0);
e.cols[entry::SIZE] = apply_attrs (size, 0);
char buf[32] = "";
auto tm = localtime (&info.st_mtime);
strftime (buf, sizeof buf,
(tm->tm_year == g.now.tm_year) ? "%b %e %H:%M" : "%b %e %Y", tm);
r.cols[row::MTIME] = apply_attrs (to_wide (buf), 0);
e.cols[entry::MTIME] = apply_attrs (to_wide (buf), 0);
// TODO: show symlink target: check st_mode/DT_*, readlink
auto format = ls_format (filename, info);
r.cols[row::FILENAME] = apply_attrs (to_wide (filename), format);
return r;
auto &fn = e.cols[entry::FILENAME] =
apply_attrs (to_wide (e.filename), ls_format (e.filename, info));
if (!e.target_path.empty ()) {
fn.append (apply_attrs (to_wide (" -> "), 0));
fn.append (apply_attrs (to_wide (e.target_path),
ls_format (e.target_path, e.target_info)));
}
return e;
}
fun inline visible_lines () -> int { return max (0, LINES - 2); }
fun update () {
int start_column = g.full_view ? 0 : row::FILENAME;
static int alignment[row::COLUMNS] = { -1, -1, -1, 1, -1, -1 };
int start_column = g.full_view ? 0 : entry::FILENAME;
static int alignment[entry::COLUMNS] = { -1, -1, -1, 1, -1, -1 };
erase ();
int available = visible_lines ();
@ -435,8 +466,8 @@ fun update () {
move (available - used + i, 0);
auto used = 0;
for (int col = start_column; col < row::COLUMNS; col++) {
const auto &field = g.entries[index].row.cols[col];
for (int col = start_column; col < entry::COLUMNS; col++) {
const auto &field = g.entries[index].cols[col];
auto aligned = align (field, alignment[col] * g.max_widths[col]);
if (selected)
for_each (begin (aligned), end (aligned), decolor);
@ -481,41 +512,17 @@ fun reload () {
g.entries.clear ();
while (auto f = readdir (dir)) {
// Two dots are for navigation but this ain't as useful
if (f->d_name == string ("."))
continue;
// TODO: check lstat() return value
// TODO: benchmark just readdir() vs. lstat(), also on dead mounts;
// it might make sense to stat asynchronously in threads
// http://lkml.iu.edu/hypermail//linux/kernel/0804.3/1616.html
struct stat sb = {};
lstat (f->d_name, &sb);
auto row = make_row (f->d_name, sb);
if (S_ISLNK (sb.st_mode)) {
char buf[PATH_MAX] = {};
auto len = readlink (f->d_name, buf, sizeof buf);
if (len < 0 || size_t (len) >= sizeof buf) {
buf[0] = '?';
buf[1] = 0;
}
struct stat sbt = {};
lstat (buf, &sbt);
row.cols[row::FILENAME].append (apply_attrs (to_wide (" -> "), 0))
.append (apply_attrs (to_wide (buf), ls_format (buf, sbt)));
}
g.entries.push_back ({ f->d_name, sb, row });
if (f->d_name != string ("."))
g.entries.push_back (make_entry (f));
}
closedir (dir);
sort (begin (g.entries), end (g.entries));
g.out_of_date = false;
for (int col = 0; col < row::COLUMNS; col++) {
for (int col = 0; col < entry::COLUMNS; col++) {
auto &longest = g.max_widths[col] = 0;
for (const auto &entry : g.entries)
longest = max (longest, compute_width (entry.row.cols[col]));
longest = max (longest, compute_width (entry.cols[col]));
}
g.cursor = min (g.cursor, int (g.entries.size ()) - 1);
@ -577,18 +584,9 @@ fun change_dir (const string& path) {
}
fun choose (const entry &entry) -> bool {
bool is_dir = S_ISDIR (entry.info.st_mode) != 0;
// Dive into directories and accessible symlinks to them
// TODO: we probably want to use a preread readlink value
if (S_ISLNK (entry.info.st_mode)) {
char buf[PATH_MAX];
struct stat sb = {};
auto len = readlink (entry.filename.c_str (), buf, sizeof buf);
is_dir = len > 0 && size_t (len) < sizeof buf
&& !stat (entry.filename.c_str (), &sb)
&& S_ISDIR (sb.st_mode) != 0;
}
if (!is_dir) {
if (!S_ISDIR (entry.info.st_mode)
&& !S_ISDIR (entry.target_info.st_mode)) {
g.chosen = entry.filename;
return false;
}