[groff] 07/15: [libgroff]: Tweak code style.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 527bdf0df6e7539a91b941af9355c7e95dfcbc24
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Fri Sep 17 15:10:48 2021 +1000

    [libgroff]: Tweak code style.
    
    * src/libs/libgroff/font.cpp (trim_args, font::load, font::load_desc):
      Compare pointer explicitly to null pointer literal `0` instead of
      using logical complementation.
    
      (font::load, font::load_desc): Swap order of null pointer equality
      comparisons when a typo or thinko could lead to lvalue assignment.
---
 ChangeLog                  | 11 +++++++++++
 src/libs/libgroff/font.cpp | 42 +++++++++++++++++++++---------------------
 2 files changed, 32 insertions(+), 21 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 900968b..102b2d0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,16 @@
 2021-09-17  G. Branden Robinson <g.branden.robinson@gmail.com>
 
+       [libgroff]: Tweak code style.
+
+       * src/libs/libgroff/font.cpp (trim_args, font::load,
+       font::load_desc): Compare pointer explicitly to null pointer
+       literal `0` instead of using logical complementation.
+       (font::load, font::load_desc): Swap order of null pointer
+       equality comparisons when a typo or thinko could lead to lvalue
+       assignment.
+
+2021-09-17  G. Branden Robinson <g.branden.robinson@gmail.com>
+
        [libgroff]: Use idiomatic C++98 null pointer constant.
 
        * src/libs/libgroff/font.cpp (text_file::error,
diff --git a/src/libs/libgroff/font.cpp b/src/libs/libgroff/font.cpp
index f4ff387..191e861 100644
--- a/src/libs/libgroff/font.cpp
+++ b/src/libs/libgroff/font.cpp
@@ -693,7 +693,7 @@ font *font::load_font(const char *s, int *not_found, bool 
head_only)
 
 static char *trim_arg(char *p)
 {
-  if (!p)
+  if (0 == p)
     return 0;
   while (csspace(*p))
     p++;
@@ -790,7 +790,7 @@ bool font::load(int *not_found, bool head_only)
     else if (strcmp(p, "spacewidth") == 0) {
       p = strtok(0, WS);
       int n;
-      if (p == 0 || sscanf(p, "%d", &n) != 1 || n <= 0) {
+      if (0 == p || sscanf(p, "%d", &n) != 1 || n <= 0) {
        t.error("bad argument for 'spacewidth' command");
        return false;
       }
@@ -799,7 +799,7 @@ bool font::load(int *not_found, bool head_only)
     else if (strcmp(p, "slant") == 0) {
       p = strtok(0, WS);
       double n;
-      if (p == 0 || sscanf(p, "%lf", &n) != 1 || n >= 90.0 || n <= -90.0) {
+      if (0 == p || sscanf(p, "%lf", &n) != 1 || n >= 90.0 || n <= -90.0) {
        t.error("bad argument for 'slant' command", p);
        return false;
       }
@@ -808,7 +808,7 @@ bool font::load(int *not_found, bool head_only)
     else if (strcmp(p, "ligatures") == 0) {
       for (;;) {
        p = strtok(0, WS);
-       if (p == 0 || strcmp(p, "0") == 0)
+       if (0 == p || strcmp(p, "0") == 0)
          break;
        if (strcmp(p, "ff") == 0)
          ligatures |= LIG_ff;
@@ -828,7 +828,7 @@ bool font::load(int *not_found, bool head_only)
     }
     else if (strcmp(p, "internalname") == 0) {
       p = strtok(0, WS);
-      if (!p) {
+      if (0 == p) {
        t.error("'internalname' command requires argument");
        return false;
       }
@@ -847,7 +847,7 @@ bool font::load(int *not_found, bool head_only)
       break;
   }
   bool had_charset = false;
-  if (p == 0) {
+  if (0 == p) {
     if (!is_unicode) {
       t.error("missing charset command");
       return false;
@@ -866,15 +866,15 @@ bool font::load(int *not_found, bool head_only)
            break;
          }
          char *c1 = strtok(t.buf, WS);
-         if (c1 == 0)
+         if (0 == c1)
            continue;
          char *c2 = strtok(0, WS);
-         if (c2 == 0) {
+         if (0 == c2) {
            command = c1;
            break;
          }
          p = strtok(0, WS);
-         if (p == 0) {
+         if (0 == p) {
            t.error("missing kern amount");
            return false;
          }
@@ -902,7 +902,7 @@ bool font::load(int *not_found, bool head_only)
          if (nm == 0)
            continue;                   // I dont think this should happen
          p = strtok(0, WS);
-         if (p == 0) {
+         if (0 == p) {
            command = nm;
            break;
          }
@@ -935,7 +935,7 @@ bool font::load(int *not_found, bool head_only)
              return false;
            }
            p = strtok(0, WS);
-           if (p == 0) {
+           if (0 == p) {
              t.error("missing character type for '%1'", nm);
              return false;
            }
@@ -950,7 +950,7 @@ bool font::load(int *not_found, bool head_only)
            }
            metric.type = type;
            p = strtok(0, WS);
-           if (p == 0) {
+           if (0 == p) {
              t.error("missing code for '%1'", nm);
              return false;
            }
@@ -1048,7 +1048,7 @@ bool font::load_desc()
        directive_found = true;
     if (directive_found) {
       char *q = strtok(0, WS);
-      if (!q) {
+      if (0 == q) {
        t.error("missing value for command '%1'", p);
        return false;
       }
@@ -1061,7 +1061,7 @@ bool font::load_desc()
     }
     else if (strcmp("family", p) == 0) {
       p = strtok(0, WS);
-      if (!p) {
+      if (0 == p) {
        t.error("family command requires an argument");
        return false;
       }
@@ -1071,14 +1071,14 @@ bool font::load_desc()
     }
     else if (strcmp("fonts", p) == 0) {
       p = strtok(0, WS);
-      if (!p || sscanf(p, "%d", &nfonts) != 1 || nfonts <= 0) {
+      if (0 == p || sscanf(p, "%d", &nfonts) != 1 || nfonts <= 0) {
        t.error("bad number of fonts '%1'", p);
        return false;
       }
-      font_name_table = (const char **)new char *[nfonts+1]; 
+      font_name_table = (const char **)new char *[nfonts+1];
       for (int i = 0; i < nfonts; i++) {
        p = strtok(0, WS);
-       while (p == 0) {
+       while (0 == p) {
          if (!t.next_line()) {
            t.error("end of file while reading list of fonts");
            return false;
@@ -1098,7 +1098,7 @@ bool font::load_desc()
     }
     else if (strcmp("papersize", p) == 0) {
       p = strtok(0, WS);
-      if (!p) {
+      if (0 == p) {
        t.error("papersize command requires an argument");
        return false;
       }
@@ -1129,7 +1129,7 @@ bool font::load_desc()
       int i = 0;
       for (;;) {
        p = strtok(0, WS);
-       while (p == 0) {
+       while (0 == p) {
          if (!t.next_line()) {
            t.error("list of sizes must be terminated by '0'");
            return false;
@@ -1175,7 +1175,7 @@ bool font::load_desc()
       int i = 0;
       for (;;) {
        p = strtok(0, WS);
-       if (p == 0)
+       if (0 == p)
          break;
        // leave room for terminating 0
        if (i + 1 >= style_table_size) {
@@ -1201,7 +1201,7 @@ bool font::load_desc()
       is_unicode = true;
     else if (strcmp("image_generator", p) == 0) {
       p = strtok(0, WS);
-      if (!p) {
+      if (0 == p) {
        t.error("image_generator command requires an argument");
        return false;
       }