Fix printf hack in the bindings (#152)

.cirrus.yml

@@ -46,7 +46,7 @@ ruby_freebsd_task:
     CPATH: '/usr/local/include'
     LIBRARY_PATH: '/usr/local/lib'
   dependencies_script:
-    - pkg install --yes autoconf automake git libtool wget
+    - pkg install --yes autoconf automake cppcheck git libtool wget
   dependencies_ruby_script:
     - wget https://cache.ruby-lang.org/pub/ruby/3.0/ruby-3.0.3.tar.gz
     - tar -xzf ruby-3.0.3.tar.gz

.github/workflows/mruby.yml

@@ -46,6 +46,3 @@ jobs:
       - working-directory: bindings/mruby
         name: lint
         run: rake
-      - working-directory: bindings/mruby
-        name: cppcheck
-        run: cppcheck --quiet --error-exitcode=1 --std=c99 --enable=warning,style,performance,portability .

.github/workflows/ruby.yml

@@ -44,6 +44,3 @@ jobs:
       - working-directory: bindings/ruby
         name: test & lint
         run: SKIP_COVERAGE='${{matrix.packages.skip_coverage}}' rake
-      - working-directory: bindings/ruby
-        name: cppcheck
-        run: cppcheck --quiet --error-exitcode=1 --std=c99 --enable=warning,style,performance,portability .

README.md

@@ -202,6 +202,12 @@ make
 
 You can test with `make check`.
 
+#### See also
+
+* [GitHub Actions](/.github/) for **GNU/Linux** build environment
+* [Cirrus CI](/.cirrus.yml) for **FreeBSD** build environment
+* [sourcehut CI](/.openbsd.yml) for **OpenBSD** build environment
+
 ### Cross
 
 Create configuration script with `./autogen.sh` (if present).

bindings/mruby/Rakefile

@@ -4,7 +4,7 @@ desc 'Run default checks'
 task default: :lint
 
 desc 'Run code analysis tools'
-task lint: :rubocop
+task lint: %i[rubocop cppcheck]
 
 desc 'Fix code style (rubocop --auto-correct)'
 task fix: 'rubocop:auto_correct'
@@ -15,3 +15,15 @@ begin
 rescue LoadError
   nil
 end
+
+desc 'Run cppcheck'
+task :cppcheck do
+  sh(
+    'cppcheck',
+    '--quiet',
+    '--error-exitcode=1',
+    '--std=c99',
+    '--enable=warning,style,performance,portability',
+    __dir__,
+  )
+end

bindings/mruby/src/assert.c

@@ -1,8 +1,5 @@
 #include "main.h"
 
-#include <stddef.h>
-#include <string.h>
-
 #include <mruby/presym.h>
 #include <mruby/string.h>
 #include <mruby/variable.h>

bindings/mruby/src/cmdline.c

@@ -1,9 +1,5 @@
 #include "main.h"
 
-#include <stdbool.h>
-#include <stddef.h>
-#include <stdlib.h>
-
 #include <mruby/array.h>
 #include <mruby/presym.h>
 #include <mruby/string.h>

bindings/mruby/src/main.h

@@ -4,6 +4,12 @@
 #include <kernaux.h>
 #include <mruby.h>
 
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
 void current_mrb_start(mrb_state *mrb);
 void current_mrb_finish(mrb_state *mrb);
 mrb_state *current_mrb_get();

bindings/mruby/src/ntoa.c

@@ -1,7 +1,5 @@
 #include "main.h"
 
-#include <stdint.h>
-
 #include <mruby/numeric.h>
 #include <mruby/presym.h>
 #include <mruby/string.h>

bindings/mruby/src/printf.c

@@ -29,8 +29,7 @@ void init_printf(mrb_state *const mrb)
 
 mrb_value rb_KernAux_sprintf(mrb_state *const mrb, mrb_value self)
 {
-    // FIXME: const
-    char *format;
+    const char *format;
     mrb_value *args;
     mrb_int argc;
     mrb_get_args(mrb, "z*", &format, &args, &argc);
@@ -45,12 +44,9 @@ mrb_value rb_KernAux_sprintf(mrb_state *const mrb, mrb_value self)
             continue;
         }
 
-        // FIXME: unnecessary
-        const char *const old_format = format;
         ++format;
         struct KernAux_PrintfFmt_Spec spec =
-            // FIXME: no type cast
-            KernAux_PrintfFmt_Spec_create_out((const char**)&format);
+            KernAux_PrintfFmt_Spec_create_out(&format);
 
         if (spec.set_width) {
             TAKE_ARG;
@@ -87,14 +83,16 @@ mrb_value rb_KernAux_sprintf(mrb_state *const mrb, mrb_value self)
             DynArg_use_str(&dynarg, RSTRING_CSTR(mrb, arg_rb));
         }
 
+        // 1 additional byte for the '%' character.
+        // 1 additional byte for the terminating '\0' character.
+        char old_format[2 + spec.format_limit - spec.format_start];
+        memset(old_format, '\0', sizeof(old_format));
+        old_format[0] = '%';
+        strncpy(&old_format[1], spec.format_start, sizeof(old_format) - 2);
+
         char buffer[BUFFER_SIZE];
         int slen;
 
-        // FIXME: it's a hack
-        // TODO: convert printf format spec to string
-        const char tmp = *format;
-        *format = '\0';
-
         if (spec.set_width) {
             if (spec.set_precision) {
                 if (dynarg.use_dbl) {
@@ -133,7 +131,6 @@ mrb_value rb_KernAux_sprintf(mrb_state *const mrb, mrb_value self)
             }
         }
 
-        *format = tmp;
         mrb_str_cat(mrb, result, buffer, slen);
     }
 

bindings/ruby/Rakefile

@@ -20,13 +20,13 @@ CLEAN << 'doc'
 CLEAN << 'spec/examples.txt'
 
 desc 'Run default checks'
-task default: %i[test lint yard:cov]
+task default: %i[test lint]
 
 desc 'Run tests'
 task test: :spec
 
 desc 'Run code analysis tools'
-task lint: :rubocop
+task lint: %i[rubocop cppcheck yard:cov]
 
 desc 'Fix code style (rubocop --auto-correct)'
 task fix: 'rubocop:auto_correct'
@@ -66,6 +66,18 @@ task :console do
   sh 'bundle', 'exec', File.expand_path(File.join('bin', 'console'), __dir__)
 end
 
+desc 'Run cppcheck'
+task :cppcheck do
+  sh(
+    'cppcheck',
+    '--quiet',
+    '--error-exitcode=1',
+    '--std=c99',
+    '--enable=warning,style,performance,portability',
+    __dir__,
+  )
+end
+
 namespace :yard do
   desc 'Measure documentation coverage'
   task :cov do

bindings/ruby/ext/default/main.h

@@ -4,6 +4,12 @@
 #include <kernaux.h>
 #include <ruby.h>
 
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
 extern ID rb_intern_call;
 extern ID rb_intern_freeze;
 extern ID rb_intern_LESS;

bindings/ruby/ext/default/printf.c

@@ -31,8 +31,7 @@ VALUE rb_KernAux_sprintf(const int argc, VALUE *const argv, VALUE self)
 {
     if (argc == 0) rb_raise(rb_eArgError, "too few arguments");
 
-    // FIXME: const
-    char *format = StringValueCStr(argv[0]);
+    const char *format = StringValueCStr(argv[0]);
     int arg_index = 1;
     VALUE result = rb_str_new_literal("");
 
@@ -43,12 +42,9 @@ VALUE rb_KernAux_sprintf(const int argc, VALUE *const argv, VALUE self)
             continue;
         }
 
-        // FIXME: unnecessary
-        const char *const old_format = format;
         ++format;
         struct KernAux_PrintfFmt_Spec spec =
-            // FIXME: no type cast
-            KernAux_PrintfFmt_Spec_create_out((const char**)&format);
+            KernAux_PrintfFmt_Spec_create_out(&format);
 
         if (spec.set_width) {
             TAKE_ARG;
@@ -82,14 +78,16 @@ VALUE rb_KernAux_sprintf(const int argc, VALUE *const argv, VALUE self)
             DynArg_use_str(&dynarg, StringValueCStr(arg_rb));
         }
 
+        // 1 additional byte for the '%' character.
+        // 1 additional byte for the terminating '\0' character.
+        char old_format[2 + spec.format_limit - spec.format_start];
+        memset(old_format, '\0', sizeof(old_format));
+        old_format[0] = '%';
+        strncpy(&old_format[1], spec.format_start, sizeof(old_format) - 2);
+
         char buffer[BUFFER_SIZE];
         int slen;
 
-        // FIXME: it's a hack
-        // TODO: convert printf format spec to string
-        const char tmp = *format;
-        *format = '\0';
-
         if (spec.set_width) {
             if (spec.set_precision) {
                 if (dynarg.use_dbl) {
@@ -128,7 +126,6 @@ VALUE rb_KernAux_sprintf(const int argc, VALUE *const argv, VALUE self)
             }
         }
 
-        *format = tmp;
         rb_str_cat(result, buffer, slen);
     }