[groff] 57/80: [grolj4]: Align with modern groff conventions.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit da796a2c47c5b999ad5a568e69b4394f2bfecfdc
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Thu Nov 28 22:02:30 2024 -0600

    [grolj4]: Align with modern groff conventions.
    
    * src/devices/grolj4/lj4.cpp (lj4_font::handle_unknown_font_command):
      Use libgroff's newfangled `array_length()` template function to
      measure arrays.
    
      (lj4_font::handle_unknown_font_command, lj4_printer::draw, main):
      Recast wording of diagnostic messages.
    
      (main): Use standard symbol `EXIT_SUCCESS` instead of `0` literal.
      Replace `assert(0)` call with communicative predicate.
    
      (usage): If asked for `--help`, summarize command purpose in message.
---
 ChangeLog                  | 14 +++++++++++
 src/devices/grolj4/lj4.cpp | 63 +++++++++++++++++++++++++++++-----------------
 2 files changed, 54 insertions(+), 23 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 0f5ccbbc6..aa299fa86 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2024-11-28  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       [grolj4]: Align with modern groff conventions.
+
+       * src/devices/grolj4/lj4.cpp
+       (lj4_font::handle_unknown_font_command): Use libgroff's
+       newfangled `array_length()` template function to measure arrays.
+       (lj4_font::handle_unknown_font_command, lj4_printer::draw)
+       (main): Recast wording of diagnostic messages.
+       (main): Use standard symbol `EXIT_SUCCESS` instead of `0`
+       literal.  Replace `assert(0)` call with communicative predicate.
+       (usage): If asked for `--help`, summarize command purpose in
+       message.
+
 2024-11-28  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        [post-grohtml]: Align with modern groff conventions.
diff --git a/src/devices/grolj4/lj4.cpp b/src/devices/grolj4/lj4.cpp
index cb623080e..e0aeb4816 100644
--- a/src/devices/grolj4/lj4.cpp
+++ b/src/devices/grolj4/lj4.cpp
@@ -35,6 +35,11 @@ X command to include bitmap graphics
 #endif
 
 #include <assert.h>
+#include <locale.h> // setlocale()
+#include <math.h> // atan2(), floor()
+#include <stdio.h> // EOF, FILE, fflush(), fprintf(), printf(),
+                  // setbuf(), stderr, stdout
+#include <stdlib.h> // exit(), EXIT_SUCCESS, strtol()
 
 #include "driver.h"
 #include "nonposix.h"
@@ -129,10 +134,10 @@ static struct {
 
 void lj4_font::handle_unknown_font_command(const char *command,
                                           const char *arg,
-                                          const char *filename, int lineno)
+                                          const char *filename,
+                                          int lineno)
 {
-  for (unsigned int i = 0;
-       i < sizeof(command_table)/sizeof(command_table[0]); i++) {
+  for (size_t i = 0; i < array_length(command_table); i++) {
     if (strcmp(command, command_table[i].s) == 0) {
       if (arg == 0)
        fatal_with_file_and_line(filename, lineno,
@@ -142,18 +147,20 @@ void lj4_font::handle_unknown_font_command(const char 
*command,
       long n = strtol(arg, &ptr, 10);
       if (ptr == arg)
        fatal_with_file_and_line(filename, lineno,
-                                "'%1' command requires numeric argument",
-                                command);
+                                "'%1' command requires numeric"
+                                " argument", command);
       if (n < command_table[i].min) {
        error_with_file_and_line(filename, lineno,
-                                "argument for '%1' command must not be less 
than %2",
-                                command, command_table[i].min);
+                                "'%1' command argument must not be"
+                                " less than %2", command,
+                                command_table[i].min);
        n = command_table[i].min;
       }
       else if (n > command_table[i].max) {
        error_with_file_and_line(filename, lineno,
-                                "argument for '%1' command must not be greater 
than %2",
-                                command, command_table[i].max);
+                                "'%1' command argument must not be"
+                                " greater than %2", command,
+                                command_table[i].max);
        n = command_table[i].max;
       }
       this->*command_table[i].ptr = int(n);
@@ -538,7 +545,7 @@ void lj4_printer::draw(int code, int *p, int np, const 
environment *env)
       break;
     }
   default:
-    error("unrecognised drawing command '%1'", char(code));
+    error("unrecognized drawing command '%1'", char(code));
     break;
   }
 }
@@ -631,7 +638,8 @@ int main(int argc, char **argv)
        fprintf(stderr, "duplex assumed to be long-side\n");
        duplex_flag = 1;
       } else
-       fprintf(stderr, "option -%c requires an argument\n", optopt);
+       fprintf(stderr, "command-line option '%c' requires an"
+               " argument\n", optopt);
       fflush(stderr);
       break;
     case 'd':
@@ -639,7 +647,8 @@ int main(int argc, char **argv)
        optind--;               //  args from messing up the arg list
       duplex_flag = atoi(optarg);
       if (duplex_flag != 1 && duplex_flag != 2) {
-       fprintf(stderr, "odd value for duplex; assumed to be long-side\n");
+       fprintf(stderr, "argument to command-line option 'd' out of"
+               " range; assuming long-side duplexing\n");
        duplex_flag = 1;
       }
       break;
@@ -654,7 +663,7 @@ int main(int argc, char **argv)
       }
     case 'v':
       printf("GNU grolj4 (groff) version %s\n", Version_string);
-      exit(0);
+      exit(EXIT_SUCCESS);
       break;
     case 'F':
       font::command_line_font_dir(optarg);
@@ -664,9 +673,11 @@ int main(int argc, char **argv)
        char *ptr;
        long n = strtol(optarg, &ptr, 10);
        if (ptr == optarg)
-         error("argument for -c must be a positive integer");
+         error("argument to command-line option 'c' option must be a"
+               " positive integer");
        else if (n <= 0 || n > 32767)
-         error("out of range argument for -c");
+         error("argument to command-line option 'c' out of range"
+               " [0, 32767)");
        else
          ncopies = unsigned(n);
        break;
@@ -676,16 +687,18 @@ int main(int argc, char **argv)
        char *ptr;
        long n = strtol(optarg, &ptr, 10);
        if (ptr == optarg)
-         error("argument for -w must be a non-negative integer");
+         error("argument to command-line option 'w' must be a"
+               " non-negative integer");
        else if (n < 0 || n > INT_MAX)
-         error("out of range argument for -w");
+         error("argument to command-line option 'w' out of range"
+               " (0, %1)", INT_MAX);
        else
          line_width_factor = int(n);
        break;
       }
     case CHAR_MAX + 1: // --help
       usage(stdout);
-      exit(0);
+      exit(EXIT_SUCCESS);
       break;
     case '?':
       error("unrecognized command-line option '%1'", char(optopt));
@@ -693,7 +706,7 @@ int main(int argc, char **argv)
       exit(2);
       break;
     default:
-      assert(0);
+      assert(0 == "unhandled getopt_long return value");
     }
   SET_BINARY(fileno(stdout));
   if (optind >= argc)
@@ -708,11 +721,15 @@ int main(int argc, char **argv)
 static void usage(FILE *stream)
 {
   fprintf(stream,
-         "usage: %s [-l] [-c n] [-d [n]] [-F dir] [-p paper-format]"
-         " [-w n] [file ...]\n"
-         "usage: %s {-v | --version}\n"
-         "usage: %s --help\n",
+"usage: %s [-l] [-c n] [-d [n]] [-F dir] [-p paper-format] [-w n]"
+" [file ...]\n"
+"usage: %s {-v | --version}\n"
+"usage: %s --help\n",
          program_name, program_name, program_name);
+  if (stdout == stream)
+    fputs("\n"
+"Translate the output of troff(1) into PCL 5/LaserJet 4 format.  See\n"
+"the grolj4(1) manual page.\n", stream);
 }
 
 // Local Variables: