The following adds ut/nut flags to indent to enable/disable tabs which seems to have originated in gnu indent.
-nut seems to have quite a bit of usage and is currently assumed in the Mesa3D build when generating code. Diff based on FreeBSD svn rev 131184. Unrelated to this diff there seems to be a problem with indent when run on code like { <tab>int a; } the result is: { <tab>int <tab><tab>a; } This behaviour is present without the diff and isn't addressed here. Index: args.c =================================================================== RCS file: /cvs/src/usr.bin/indent/args.c,v retrieving revision 1.15 diff -u -p -r1.15 args.c --- args.c 27 Oct 2009 23:59:39 -0000 1.15 +++ args.c 8 Apr 2013 13:27:58 -0000 @@ -135,6 +135,7 @@ struct pro { {"nps", PRO_BOOL, false, OFF, &pointer_as_binop }, {"nsc", PRO_BOOL, true, OFF, &star_comment_cont }, {"nsob", PRO_BOOL, false, OFF, &swallow_optional_blanklines }, + {"nut", PRO_BOOL, true, OFF, &use_tabs}, {"nv", PRO_BOOL, false, OFF, &verbose }, {"pcs", PRO_BOOL, false, ON, &proc_calls_space }, {"psl", PRO_BOOL, true, ON, &procnames_start_line }, @@ -143,6 +144,7 @@ struct pro { {"sob", PRO_BOOL, false, ON, &swallow_optional_blanklines }, {"st", PRO_SPECIAL, 0, STDIN, 0 }, {"troff", PRO_BOOL, false, ON, &troff }, + {"ut", PRO_BOOL, true, ON, &use_tabs}, {"v", PRO_BOOL, false, ON, &verbose }, /* whew! */ { 0, 0, 0, 0, 0 } Index: indent.1 =================================================================== RCS file: /cvs/src/usr.bin/indent/indent.1,v retrieving revision 1.20 diff -u -p -r1.20 indent.1 --- indent.1 17 Jan 2013 21:29:14 -0000 1.20 +++ indent.1 8 Apr 2013 13:28:15 -0000 @@ -71,6 +71,7 @@ .Op Fl \&st .Op Fl T Ns Ar typename .Op Fl troff +.Op Fl ut | Fl nut .Op Fl v | \&nv .Ek .Sh DESCRIPTION @@ -384,6 +385,11 @@ to format the program for processing by producing a fancy listing. If the output file is not specified, the default is standard output, rather than formatting in place. +.It Fl ut , nut +Enables (disables) the use of tab characters in the output. +Tabs are assumed to be aligned on columns divisible by 8. +The default is +.Fl ut . .It Fl v , \&nv .Fl v turns on Index: indent.c =================================================================== RCS file: /cvs/src/usr.bin/indent/indent.c,v retrieving revision 1.20 diff -u -p -r1.20 indent.c --- indent.c 27 Oct 2009 23:59:39 -0000 1.20 +++ indent.c 8 Apr 2013 13:31:06 -0000 @@ -73,6 +73,7 @@ main(int argc, char **argv) * without the matching : in a <c>?<s>:<s> * construct */ char *t_ptr; /* used for copying tokens */ + int tabs_to_var; /* true if using tabs to indent to var name */ int type_code; /* the type of token, returned by lexi */ int last_else = 0; /* true iff last keyword was an else */ @@ -891,6 +892,7 @@ check_type: * : i); */ dec_ind = ps.decl_indent > 0 ? ps.decl_indent : i; + tabs_to_var = (use_tabs ? ps.decl_indent > 0 : 0); goto copy_id; case ident: /* got an identifier or constant */ @@ -907,12 +909,43 @@ check_type: ps.dumped_decl_indent = 1; e_code += strlen(e_code); CHECK_SIZE_CODE; - } - else - while ((e_code - s_code) < dec_ind) { + } else { + int cur_dec_ind; + int pos, startpos; + + /* + * in order to get the tab math right for + * indentations that are not multiples of 8 we + * need to modify both startpos and dec_ind + * (cur_dec_ind) here by eight minus the + * remainder of the current starting column + * divided by eight. This seems to be a + * properly working fix + */ + startpos = e_code - s_code; + cur_dec_ind = dec_ind; + pos = startpos; + if ((ps.ind_level * ps.ind_size) % 8 != 0) { + pos += (ps.ind_level * ps.ind_size) % 8; + cur_dec_ind += (ps.ind_level * ps.ind_size) % 8; + } + + if (tabs_to_var) { + while ((pos & ~7) + 8 <= cur_dec_ind) { + CHECK_SIZE_CODE; + *e_code++ = '\t'; + pos = (pos & ~7) + 8; + } + } + while (pos < cur_dec_ind) { CHECK_SIZE_CODE; *e_code++ = ' '; + pos++; } + if (ps.want_blank && e_code - s_code == startpos) + *e_code++ = ' '; + ps.want_blank = false; + } } } else { Index: indent_globs.h =================================================================== RCS file: /cvs/src/usr.bin/indent/indent_globs.h,v retrieving revision 1.10 diff -u -p -r1.10 indent_globs.h --- indent_globs.h 25 Jun 2003 21:24:53 -0000 1.10 +++ indent_globs.h 8 Apr 2013 13:27:22 -0000 @@ -198,6 +198,8 @@ int extra_expression_indent; /* * indented an extra tab stop so that * they don't conflict with the code * that follows */ +int use_tabs; /* set true to use tabs for spacing, + * false uses all spaces */ /* -troff font state information */ Index: io.c =================================================================== RCS file: /cvs/src/usr.bin/indent/io.c,v retrieving revision 1.11 diff -u -p -r1.11 io.c --- io.c 27 Oct 2009 23:59:39 -0000 1.11 +++ io.c 8 Apr 2013 13:39:27 -0000 @@ -458,9 +458,11 @@ pad_output(int current, int target) if (current >= target) return (current); /* line is already long enough */ curr = current; - while ((tcur = ((curr - 1) & tabmask) + tabsize + 1) <= target) { - putc('\t', output); - curr = tcur; + if (use_tabs) { + while ((tcur = ((curr - 1) & tabmask) + tabsize + 1) <= target) { + putc('\t', output); + curr = tcur; + } } while (curr++ < target) putc(' ', output); /* pad with final blanks */