commit f34bdfc551710ed5f4936d6d7e5ef97074ad35b1
parent 972691fd53084393dad02faed6c2260aa2e19087
Author: Arun Prakash Jana <engineerarun@gmail.com>
Date: Mon, 13 Apr 2026 01:17:21 +0530
Support preview pane with <kbd>P</kbd>
Add .npreview: a previewer plugin that nnn auto-detects
Diffstat:
| A | plugins/.npreview | | | 135 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
| M | src/nnn.c | | | 295 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-- |
| M | src/nnn.h | | | 3 | +++ |
3 files changed, 428 insertions(+), 5 deletions(-)
diff --git a/plugins/.npreview b/plugins/.npreview
@@ -0,0 +1,135 @@
+#!/usr/bin/env sh
+
+# Description: Preview plugin for nnn's built-in preview pane
+# Auto-detected from plugins dir
+# Usage: .npreview <filepath> <width> <height>
+# All dependencies optional — graceful fallback to head/file/strings
+
+set -euf
+
+F="$1"
+W="${2:-80}"
+H="${3:-25}"
+ext="${F##*.}"
+ext="$(printf "%s" "$ext" | tr '[:upper:]' '[:lower:]')"
+
+has() { type "$1" >/dev/null 2>&1; }
+hd() { head -n "$H"; }
+
+# --- Handlers ---
+
+show_dir() {
+ has tree && { tree -L 1 -n --dirsfirst --noreport "$F" | hd; return; }
+ ls -1 "$F" 2>/dev/null | hd
+}
+
+show_text() {
+ has bat && { bat --style=plain --color=never --paging=never --line-range=":${H}" -- "$F" 2>/dev/null; return; }
+ has batcat && { batcat --style=plain --color=never --paging=never --line-range=":${H}" -- "$F" 2>/dev/null; return; }
+ head -n "$H" "$F"
+}
+
+show_pdf() {
+ has pdftotext && { pdftotext -l 1 -nopgbrk -q -- "$F" - 2>/dev/null | hd; return; }
+ has mutool && { mutool draw -F txt -i -- "$F" 1 2>/dev/null | hd; return; }
+ show_meta
+}
+
+show_archive() {
+ case "$ext" in
+ rar) has unrar && { unrar lt -p- -- "$F" 2>/dev/null | hd; return; } ;;
+ 7z) has 7z && { 7z l -p -- "$F" 2>/dev/null | hd; return; } ;;
+ esac
+ has atool && { atool --list -- "$F" 2>/dev/null | hd; return; }
+ has bsdtar && { bsdtar --list --file "$F" 2>/dev/null | hd; return; }
+ has tar && { tar tf "$F" 2>/dev/null | hd; return; }
+ has unzip && [ "$ext" = "zip" ] && { unzip -l "$F" 2>/dev/null | hd; return; }
+ printf "[archive %s]\n" "$(du -h "$F" 2>/dev/null | cut -f1)"
+}
+
+show_image() {
+ has img2txt && { img2txt --gamma=0.6 --width="$W" -- "$F" 2>/dev/null | hd; return; }
+ show_meta
+}
+
+show_meta() {
+ has exiftool && { exiftool "$F" 2>/dev/null | hd; return; }
+ has mediainfo && { mediainfo "$F" 2>/dev/null | hd; return; }
+ has file && { file -b "$F"; return; }
+ printf "[no metadata tool]\n"
+}
+
+show_json() {
+ has jq && { head -c 65536 "$F" | jq --monochrome-output . 2>/dev/null | hd; return; }
+ has python3 && { head -c 65536 "$F" | python3 -m json.tool 2>/dev/null | hd; return; }
+ show_text
+}
+
+show_md() {
+ has glow && { glow -s notty "$F" 2>/dev/null | hd; return; }
+ has lowdown && { lowdown -Tterm "$F" 2>/dev/null | hd; return; }
+ show_text
+}
+
+show_html() {
+ has w3m && { w3m -dump "$F" 2>/dev/null | hd; return; }
+ has lynx && { lynx -dump -- "$F" 2>/dev/null | hd; return; }
+ show_text
+}
+
+show_elf() {
+ has readelf && { readelf -h "$F" 2>/dev/null | hd; return; }
+ has objdump && { objdump -f "$F" 2>/dev/null | hd; return; }
+ has file && file -b "$F"
+}
+
+show_doc() {
+ has odt2txt && { odt2txt "$F" 2>/dev/null | hd; return; }
+ show_meta
+}
+
+show_bin() {
+ has strings && { printf "[binary]\n"; strings "$F" 2>/dev/null | hd; return; }
+ printf "[binary %s]\n" "$(du -h "$F" 2>/dev/null | cut -f1)"
+}
+
+# --- Directory ---
+[ -d "$F" ] && { show_dir; exit 0; }
+
+# --- Dispatch by extension ---
+case "$ext" in
+ a|ace|alz|arc|arj|bz|bz2|cab|cpio|deb|gz|jar|lha|lz|lzh|lzma|lzo|\
+ rpm|rz|t7z|tar|tbz|tbz2|tgz|tlz|txz|tz|tzo|war|xpi|xz|z|zip|rar|7z|zst)
+ show_archive; exit 0 ;;
+ pdf) show_pdf; exit 0 ;;
+ md|mkd|markdown) show_md; exit 0 ;;
+ htm|html|xhtml) show_html; exit 0 ;;
+ json) show_json; exit 0 ;;
+ odt|ods|odp|sxw) show_doc; exit 0 ;;
+ torrent) has transmission-show && { transmission-show -- "$F" 2>/dev/null | hd; exit 0; } ;;
+ sqlite|sqlite3|db) has sqlite3 && { printf ".tables\n" | sqlite3 "$F" 2>/dev/null | hd; exit 0; } ;;
+ o|so|dylib) show_elf; exit 0 ;;
+ c|cc|cpp|h|hpp|rs|go|py|rb|js|ts|java|sh|bash|zsh|pl|lua|vim|el|\
+ css|scss|yaml|yml|toml|ini|conf|xml|sql|diff|patch|awk|sed|make)
+ show_text; exit 0 ;;
+esac
+
+# --- Dispatch by mime type ---
+has file || { show_text; exit 0; }
+mime="$(file -bL --mime-type -- "$F" 2>/dev/null)"
+
+case "$mime" in
+ text/*|*/xml) show_text ;;
+ application/json) show_json ;;
+ application/pdf) show_pdf ;;
+ application/zip|application/x-tar|application/x-rar*|\
+ application/x-7z*|application/x-bzip*|application/x-xz|\
+ application/x-compress*|application/gzip|application/zstd)
+ show_archive ;;
+ image/*) show_image ;;
+ audio/*|video/*) show_meta ;;
+ application/x-executable|application/x-sharedlib|application/x-pie-executable|\
+ application/x-object) show_elf ;;
+ application/vnd.openxmlformats*|application/vnd.oasis.opendocument*) show_doc ;;
+ *) show_bin ;;
+esac
diff --git a/src/nnn.c b/src/nnn.c
@@ -358,7 +358,7 @@ typedef struct {
uint_t blkorder : 1; /* Set to sort by blocks used (disk usage) */
uint_t extnorder : 1; /* Order by extension */
uint_t showhidden : 1; /* Set to show hidden files */
- uint_t reserved0 : 1;
+ uint_t preview : 1; /* Show preview pane */
uint_t showdetail : 1; /* Clear to show lesser file info */
uint_t ctxactive : 1; /* Context active or not */
uint_t reverse : 1; /* Reverse sort */
@@ -477,6 +477,7 @@ static char *plgpath;
static char *pnamebuf, *pselbuf, *findselpos;
static char *mark;
static char *trashcmd;
+static char *previewer = NULL;
#ifndef NOX11
static char hostname[_POSIX_HOST_NAME_MAX + 1];
#endif
@@ -604,6 +605,7 @@ static runstate g_state;
#define UTIL_GIO_TRASH 19
#define UTIL_RM_RF 20
#define UTIL_ARCHMNT 21
+#define UTIL_NPREVIEW 22
/* Utilities to open files, run actions */
static char * const utils[] = {
@@ -645,6 +647,7 @@ static char * const utils[] = {
"gio trash",
"rm -rf --",
"archivemount",
+ ".npreview",
};
/* Common strings */
@@ -6281,9 +6284,10 @@ static void show_help(const char *path)
"1FILES\n"
"9o ^O Open with%15n Create new/link\n"
"9f ^F File stats%14d Detail mode toggle\n"
- "b^R Rename/dup%14r Batch rename\n"
- "cz Archive%17e Edit file\n"
- "c* Toggle exe%14> Export list\n"
+ "b^R Rename/dup%14P Preview toggle\n"
+ "cr Batch rename%12e Edit file\n"
+ "cz Archive%17* Toggle exe\n"
+ "c> Export list\n"
"6Space + (Un)select%12m-m Select range/clear\n"
"ca Select all%14A Invert sel\n"
"9p ^P Copy here%12w ^W Cp/mv sel as\n"
@@ -8064,6 +8068,272 @@ static inline void markhovered(void)
}
}
+#define PREVIEW_BORDER_COL (xcols / 2)
+#define PREVIEW_COL (PREVIEW_BORDER_COL + 2)
+#define PREVIEW_WIDTH (xcols - PREVIEW_COL - 1)
+#define MIN_PREVIEW_COLS 40
+#define PREVIEW_MAX_LINE 4096
+
+/* Check if a file is likely text by reading initial bytes */
+static bool is_text_file(const char *fpath)
+{
+ int fd = open(fpath, O_RDONLY);
+ if (fd == -1)
+ return FALSE;
+
+ unsigned char buf[512];
+ ssize_t n = read(fd, buf, sizeof(buf));
+ close(fd);
+
+ if (n <= 0)
+ return FALSE;
+
+ /* Reject known binary magic signatures */
+ static const struct {
+ const unsigned char bytes[8];
+ unsigned char len;
+ } magics[] = {
+ { { '%', 'P', 'D', 'F' }, 4 }, /* PDF */
+ { { 0x89, 'P', 'N', 'G' }, 4 }, /* PNG */
+ { { 'G', 'I', 'F', '8' }, 4 }, /* GIF */
+ { { 0xFF, 0xD8, 0xFF }, 3 }, /* JPEG */
+ { { 'P', 'K', 0x03, 0x04 }, 4 }, /* ZIP */
+ { { 0x7F, 'E', 'L', 'F' }, 4 }, /* ELF */
+ { { 0x1F, 0x8B }, 2 }, /* Gzip */
+ { { 'B', 'M' }, 2 }, /* BMP */
+ { { 'R', 'I', 'F', 'F' }, 4 }, /* RIFF */
+ { { 'O', 'g', 'g', 'S' }, 4 }, /* OGG */
+ { { 'f', 'L', 'a', 'C' }, 4 }, /* FLAC */
+ { { 'I', 'D', '3' }, 3 }, /* MP3 ID3 */
+ { { 0xFE, 0xED, 0xFA }, 3 }, /* Mach-O */
+ { { 0xFD, '7', 'z', 'X', 'Z', 0x00 }, 6 }, /* XZ */
+ { { '7', 'z', 0xBC, 0xAF, 0x27, 0x1C }, 6 }, /* 7z */
+ { { 'S', 'Q', 'L', 'i', 't', 'e' }, 6 }, /* SQLite */
+ };
+
+ for (size_t i = 0; i < sizeof(magics) / sizeof(magics[0]); ++i) {
+ if (n >= magics[i].len
+ && !memcmp(buf, magics[i].bytes, magics[i].len))
+ return FALSE;
+ }
+
+ /* MP3 sync word (needs mask check) */
+ if (n >= 2 && buf[0] == 0xFF && (buf[1] & 0xE0) == 0xE0)
+ return FALSE;
+
+ /* Check for NUL bytes and non-text control characters */
+ for (ssize_t i = 0; i < n; ++i) {
+ unsigned char c = buf[i];
+ if (c == '\0')
+ return FALSE;
+ /* Reject most control chars except common text ones */
+ if (c < 0x20 && c != '\n' && c != '\r' && c != '\t'
+ && c != '\f' && c != '\033') /* ESC for ANSI */
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+/* Draw the preview pane for the currently hovered file */
+static void preview_pane(const char *path)
+{
+ if (!ndents || !cfg.preview)
+ return;
+
+ int previewcol = PREVIEW_BORDER_COL;
+ int previewwidth = PREVIEW_WIDTH;
+
+ if (previewwidth < MIN_PREVIEW_COLS)
+ return;
+
+ /* Draw vertical border */
+ for (int i = 0; i < xlines - 1; ++i) {
+ move(i, previewcol);
+ addch(ACS_VLINE | A_DIM);
+ }
+
+ char fpath[PATH_MAX];
+ mkpath(path, pdents[cur].name, fpath);
+
+ /* Auto-detect .npreview plugin */
+ if (!previewer) {
+ previewer = malloc(xstrlen(plgpath) + xstrlen(utils[UTIL_NPREVIEW]) + 1);
+ mkpath(plgpath, utils[UTIL_NPREVIEW], previewer);
+ if (access(previewer, X_OK)) {
+ free(previewer);
+ previewer = NULL;
+ }
+ }
+
+ if (previewer) {
+ int pipefd[2];
+ if (pipe(pipefd) == -1)
+ return;
+
+ pid_t pid = fork();
+ if (pid == 0) {
+ close(pipefd[0]);
+ dup2(pipefd[1], STDOUT_FILENO);
+ dup2(pipefd[1], STDERR_FILENO);
+ close(pipefd[1]);
+
+ char widthbuf[16], heightbuf[16];
+ snprintf(widthbuf, sizeof(widthbuf), "%d", previewwidth);
+ snprintf(heightbuf, sizeof(heightbuf), "%d", xlines - 2);
+
+ execlp(previewer, previewer, fpath,
+ widthbuf, heightbuf,
+ (char *)NULL);
+ _exit(EXIT_FAILURE);
+ }
+ close(pipefd[1]);
+
+ if (pid > 0) {
+ FILE *fp = fdopen(pipefd[0], "r");
+ if (fp) {
+ char line[PREVIEW_MAX_LINE];
+ int row = 1;
+ int maxrows = xlines - 2;
+
+ while (row < maxrows && fgets(line, sizeof(line), fp)) {
+ size_t len = xstrlen(line);
+ if (len > 0 && line[len - 1] == '\n')
+ line[--len] = '\0';
+ if (len > 0 && line[len - 1] == '\r')
+ line[--len] = '\0';
+
+ /* Replace tabs with spaces */
+ for (size_t i = 0; i < len; ++i)
+ if (line[i] == '\t')
+ line[i] = ' ';
+
+ /* Wrap long lines across multiple rows */
+ int off = 0;
+ do {
+ char save = '\0';
+ if ((int)(len - off) > previewwidth) {
+ save = line[off + previewwidth];
+ line[off + previewwidth] = '\0';
+ }
+ mvaddstr(row, PREVIEW_COL, line + off);
+ if (save)
+ line[off + previewwidth] = save;
+ ++row;
+ off += previewwidth;
+ } while (off < (int)len && row < maxrows);
+ }
+ fclose(fp);
+ } else {
+ close(pipefd[0]);
+ }
+ waitpid(pid, NULL, 0);
+ } else {
+ close(pipefd[0]);
+ }
+ return;
+ }
+
+ struct stat sb;
+ if (lstat(fpath, &sb) == -1)
+ return;
+
+ /* For directories, show entry count */
+ if (S_ISDIR(sb.st_mode)) {
+ DIR *dirp = opendir(fpath);
+ if (!dirp)
+ return;
+
+ int count = 0;
+ struct dirent *dp;
+ char namebuf[PATH_MAX];
+ int maxlines = xlines - 4; /* Leave header and status lines */
+
+ mvaddstr(1, PREVIEW_COL, "[directory]");
+
+ while ((dp = readdir(dirp)) && count < maxlines) {
+ if (dp->d_name[0] == '.' && (!dp->d_name[1]
+ || (dp->d_name[1] == '.' && !dp->d_name[2])))
+ continue;
+ snprintf(namebuf, sizeof(namebuf), "%.*s",
+ previewwidth, dp->d_name);
+ mvaddstr(2 + count, PREVIEW_COL, namebuf);
+ ++count;
+ }
+ closedir(dirp);
+ return;
+ }
+
+ /* For symlinks, resolve and show target */
+ if (S_ISLNK(sb.st_mode)) {
+ char target[PATH_MAX];
+ ssize_t len = readlink(fpath, target, sizeof(target) - 1);
+ if (len > 0) {
+ target[len] = '\0';
+ mvprintw(1, PREVIEW_COL, "-> %.*s", previewwidth - 3, target);
+ }
+ /* Resolve symlink for further preview */
+ if (stat(fpath, &sb) == -1)
+ return;
+ if (!S_ISREG(sb.st_mode))
+ return;
+ }
+
+ /* For regular files, show content preview if text */
+ if (S_ISREG(sb.st_mode)) {
+ if (sb.st_size == 0) {
+ mvaddstr(1, PREVIEW_COL, "[empty file]");
+ return;
+ }
+
+ if (!is_text_file(fpath)) {
+ char szbuf[32];
+ mvprintw(1, PREVIEW_COL, "[binary %s]",
+ coolsize(sb.st_size));
+ (void)szbuf;
+ return;
+ }
+
+ FILE *fp = fopen(fpath, "r");
+ if (!fp)
+ return;
+
+ char line[PREVIEW_MAX_LINE];
+ int row = 1;
+ int maxrows = xlines - 2; /* Leave top and bottom lines */
+
+ while (row < maxrows && fgets(line, sizeof(line), fp)) {
+ /* Strip trailing newline */
+ size_t len = xstrlen(line);
+ if (len > 0 && line[len - 1] == '\n')
+ line[--len] = '\0';
+ if (len > 0 && line[len - 1] == '\r')
+ line[--len] = '\0';
+
+ /* Replace tabs with spaces for consistent display */
+ for (size_t i = 0; i < len; ++i)
+ if (line[i] == '\t')
+ line[i] = ' ';
+
+ /* Wrap long lines across multiple rows */
+ int off = 0;
+ do {
+ char save = '\0';
+ if ((int)(len - off) > previewwidth) {
+ save = line[off + previewwidth];
+ line[off + previewwidth] = '\0';
+ }
+ mvaddstr(row, PREVIEW_COL, line + off);
+ if (save)
+ line[off + previewwidth] = save;
+ ++row;
+ off += previewwidth;
+ } while (off < (int)len && row < maxrows);
+ }
+ fclose(fp);
+ }
+}
+
static int adjust_cols(int n)
{
/* Calculate the number of cols available to print entry name */
@@ -8123,13 +8393,20 @@ static void redraw(char *path)
getmaxyx(stdscr, xlines, xcols);
int ncols = (xcols <= PATH_MAX) ? xcols : PATH_MAX;
+ /* Limit listing width when preview pane is active */
+ if (cfg.preview && xcols >= (MIN_PREVIEW_COLS * 2 + 1)) {
+ int listcols = PREVIEW_BORDER_COL;
+ if (ncols > listcols)
+ ncols = listcols;
+ }
int i, j = 1;
// Fast redraw
if (g_state.move) {
g_state.move = 0;
- if (ndents && (last_curscroll == curscroll))
+ if (ndents && (last_curscroll == curscroll)
+ && !cfg.preview)
return draw_line(ncols);
}
@@ -8252,6 +8529,9 @@ static void redraw(char *path)
}
markhovered();
+
+ if (cfg.preview)
+ preview_pane(path);
}
static bool cdprep(char *lastdir, char *lastname, char *path, char *newpath)
@@ -8941,6 +9221,7 @@ nochange:
case SEL_MFLTR: // fallthrough
case SEL_HIDDEN: // fallthrough
case SEL_DETAIL: // fallthrough
+ case SEL_PREVIEW: // fallthrough
case SEL_SORT:
switch (sel) {
case SEL_MFLTR:
@@ -8966,6 +9247,9 @@ nochange:
cfg.showdetail ^= 1;
cfg.blkorder = 0;
continue;
+ case SEL_PREVIEW:
+ cfg.preview ^= 1;
+ continue;
default: /* SEL_SORT */
r = set_sort_flags(get_input(messages[MSG_ORDER]));
if (!r) {
@@ -10083,6 +10367,7 @@ static void cleanup(void)
free(dir_dispatched_bmp);
free(bookmark);
free(plug);
+ free(previewer);
if (lastcmdpos != INVALID_POS)
for (uchar_t pos = 0; pos <= lastcmdpos; ++pos)
free(cmd_hist[pos]);
diff --git a/src/nnn.h b/src/nnn.h
@@ -113,6 +113,7 @@ enum action {
SEL_SESSIONS,
SEL_EXPORT,
SEL_TIMETYPE,
+ SEL_PREVIEW,
SEL_QUITCTX,
SEL_QUITCD,
SEL_QUIT,
@@ -276,6 +277,8 @@ static struct key bindings[] = {
{ '>', SEL_EXPORT },
/* Set time type */
{ 'T', SEL_TIMETYPE },
+ /* Toggle preview pane */
+ { 'P', SEL_PREVIEW },
/* Quit a context */
{ 'q', SEL_QUITCTX },
/* Change dir on quit */
