1 files changed, 148 insertions, 0 deletions
diff --git a/runtime/autoload/man.vim b/runtime/autoload/man.vim
new file mode 100644
index 0000000000..cfd0d35a71
--- /dev/null
+++ b/runtime/autoload/man.vim
@@ -0,0 +1,148 @@
+let s:man_tag_depth = 0
+let s:man_sect_arg = ''
+let s:man_find_arg = '-w'
+
+try
+  if !has('win32') && $OSTYPE !~? 'cygwin\|linux' && system('uname -s') =~? 'SunOS' && system('uname -r') =~? '^5'
+    let s:man_sect_arg = '-s'
+    let s:man_find_arg = '-l'
+  endif
+catch /E145:/
+  " Ignore the error in restricted mode
+endtry
+
+function man#get_page(...) abort
+  let invoked_from_man = (&filetype ==# 'man')
+
+  if a:0 == 0
+    echoerr 'argument required'
+    return
+  elseif a:0 > 2
+    echoerr 'too many arguments'
+    return
+  elseif a:0 == 2
+    let [page, sect] = [a:2, 0 + a:1]
+  elseif type(1) == type(a:1)
+    let [page, sect] = ['<cword>', a:1]
+  else
+    let [page, sect] = [a:1, '']
+  endif
+
+  if page == '<cword>'
+    let page = expand('<cword>')
+  endif
+
+  let [page, sect] = s:parse_page_and_section(sect, page)
+
+  if 0 + sect > 0 && s:find_page(sect, page) == 0
+    let sect = ''
+  endif
+
+  if s:find_page(sect, page) == 0
+    echo 'No manual entry for '.page
+    return
+  endif
+
+  exec 'let s:man_tag_buf_'.s:man_tag_depth.' = '.bufnr('%')
+  exec 'let s:man_tag_lin_'.s:man_tag_depth.' = '.line('.')
+  exec 'let s:man_tag_col_'.s:man_tag_depth.' = '.col('.')
+  let s:man_tag_depth = s:man_tag_depth + 1
+
+  " Use an existing "man" window if it exists, otherwise open a new one.
+  if !invoked_from_man
+    let thiswin = winnr()
+    wincmd b
+    if winnr() > 1
+      exe "norm! " . thiswin . "\<C-W>w"
+      while 1
+        if &filetype == 'man'
+          break
+        endif
+        wincmd w
+        if thiswin == winnr()
+          break
+        endif
+      endwhile
+    endif
+    if !invoked_from_man
+      tabnew
+      let invoked_from_man = 1
+    endif
+  endif
+
+  silent exec 'edit man://'.page.(empty(sect)?'':'('.sect.')')
+
+  setlocal modifiable
+  silent keepjumps norm! 1G"_dG
+  let $MANWIDTH = winwidth(0)
+  silent exec 'r!/usr/bin/man '.s:cmd(sect, page).' | col -b'
+  " Remove blank lines from top and bottom.
+  while getline(1) =~ '^\s*$'
+    silent keepjumps norm! gg"_dd
+  endwhile
+  while getline('$') =~ '^\s*$'
+    silent keepjumps norm! G"_dd
+  endwhile
+  setlocal nomodified
+  setlocal filetype=man
+
+  if invoked_from_man
+    call s:set_window_local_options()
+  endif
+endfunction
+
+function s:set_window_local_options() abort
+  setlocal colorcolumn=0 foldcolumn=0 nonumber
+  setlocal nolist norelativenumber nofoldenable
+endfunction
+
+function man#pop_page() abort
+  if s:man_tag_depth > 0
+    let s:man_tag_depth = s:man_tag_depth - 1
+    exec "let s:man_tag_buf=s:man_tag_buf_".s:man_tag_depth
+    exec "let s:man_tag_lin=s:man_tag_lin_".s:man_tag_depth
+    exec "let s:man_tag_col=s:man_tag_col_".s:man_tag_depth
+    exec s:man_tag_buf."b"
+    exec s:man_tag_lin
+    exec "norm! ".s:man_tag_col."|"
+    exec "unlet s:man_tag_buf_".s:man_tag_depth
+    exec "unlet s:man_tag_lin_".s:man_tag_depth
+    exec "unlet s:man_tag_col_".s:man_tag_depth
+    unlet s:man_tag_buf s:man_tag_lin s:man_tag_col
+  endif
+endfunction
+
+" Expects a string like 'access' or 'access(2)'.
+function s:parse_page_and_section(sect, str) abort
+  try
+    let save_isk = &iskeyword
+    setlocal iskeyword-=(,)
+    let page = substitute(a:str, '(*\(\k\+\).*', '\1', '')
+    let sect = substitute(a:str, '\(\k\+\)(\([^()]*\)).*', '\2', '')
+    if sect == page || -1 == match(sect, '^[0-9 ]\+$')
+      let sect = a:sect
+    endif
+  catch
+    let &l:iskeyword = save_isk
+    echoerr 'man.vim: failed to parse: "'.a:str.'"'
+  endtry
+
+  return [page, sect]
+endfunction
+
+function s:cmd(sect, page) abort
+  if 0 + a:sect > 0
+    return s:man_sect_arg.' '.a:sect.' '.a:page
+  endif
+  return a:page
+endfunction
+
+function s:find_page(sect, page) abort
+  let where = system('/usr/bin/man '.s:man_find_arg.' '.s:cmd(a:sect, a:page))
+  if where !~ "^/"
+    if matchstr(where, " [^ ]*$") !~ "^ /"
+      return 0
+    endif
+  endif
+  return 1
+endfunction