[groff] 06/10: [troff]: Clamp line, title lengths to hor res.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 6e19da2ab0e360d5e48e5ef93ed32e6d703535a5
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Mon Sep 6 02:36:14 2021 +1000

    [troff]: Clamp line, title lengths to hor res.
    
    [troff]: Clamp line and title lengths to device horizontal resolution.
    
    * src/roff/troff/env.cpp (line_length, title_length): Do it.
    
    Prompted by <https://savannah.gnu.org/bugs/?61089>.
---
 ChangeLog              |  9 +++++++++
 src/roff/troff/env.cpp | 16 ++++++++++------
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 10012ba..3ec8a2b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2021-09-06  G. Branden Robinson <g.branden.robinson@gmail.com>
 
+       [troff]: Clamp line and title lengths to device horizontal
+       resolution.
+
+       * src/roff/troff/env.cpp (line_length, title_length): Do it.
+
+       Prompted by <https://savannah.gnu.org/bugs/?61089>.
+
+2021-09-06  G. Branden Robinson <g.branden.robinson@gmail.com>
+
        * src/roff/troff/env.cpp (do_hyphenation_patterns_file):
        Refactor slightly.  Demote `append` from `int` to `bool`.
        (hyphenation_patterns_file, hyphenation_patterns_file_append):
diff --git a/src/roff/troff/env.cpp b/src/roff/troff/env.cpp
index 68d0dc2..f918c57 100644
--- a/src/roff/troff/env.cpp
+++ b/src/roff/troff/env.cpp
@@ -1343,10 +1343,12 @@ void right_justify()
 void line_length()
 {
   hunits temp;
+  hunits minimum_length = font::hor;
   if (has_arg() && get_hunits(&temp, 'm', curenv->line_length)) {
-    if (temp < H0) {
-      warning(WARN_RANGE, "bad line length %1u", temp.to_units());
-      temp = H0;
+    if (temp < minimum_length) {
+      warning(WARN_RANGE, "invalid line length %1u rounded to device"
+                         " horizontal resolution", temp.to_units());
+      temp = minimum_length;
     }
   }
   else
@@ -1360,10 +1362,12 @@ void line_length()
 void title_length()
 {
   hunits temp;
+  hunits minimum_length = font::hor;
   if (has_arg() && get_hunits(&temp, 'm', curenv->title_length)) {
-    if (temp < H0) {
-      warning(WARN_RANGE, "bad title length %1u", temp.to_units());
-      temp = H0;
+    if (temp < minimum_length) {
+      warning(WARN_RANGE, "invalid title length %1u rounded to device"
+                         " horizontal resolution", temp.to_units());
+      temp = minimum_length;
     }
   }
   else