m + doc

Signed-off-by: Mattias Andrée <maandree@operamail.com>

5 files changed, 177 insertions, 127 deletions

diff --git a/src/lib/edid.c b/src/lib/edid.c
index 76867c7..800ebdd 100644
--- a/src/lib/edid.c
+++ b/src/lib/edid.c
@@ -35,45 +35,72 @@
 int libgamma_parse_edid(libgamma_crtc_information_t* restrict this, int32_t fields)
 {
 #define __test_version(edid, major, minor)  (((edid)[18] == major) && ((edid)[19] == minor))
+#define __m(value)  (this->edid[index++] != value)
   
   int error = 0;
   int checksum = 0;
-  size_t i;
+  size_t i, index = 0;
   
+  /* If the length of the EDID is not 128 bytes, we know that it is not of
+     EDID structure revision 1.3, and thus we do not support it. Additionally
+     this make sure we do not do segmentation violation on the next test. */
   if (this->edid_length != 128)
     error = LIBGAMMA_EDID_LENGTH_UNSUPPORTED;
-  else if ((this->edid[0] != 0x00) || (this->edid[1] != 0xFF) || (this->edid[2] != 0xFF) || (this->edid[3] != 0xFF) ||
-	   (this->edid[4] != 0xFF) || (this->edid[5] != 0xFF) || (this->edid[6] != 0xFF) || (this->edid[7] != 0x00))
+  /* Check that the magic number of that of the EDID structure. */
+  else if (__m(0x00) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0xFF) || __m(0x00))
     error = LIBGAMMA_EDID_WRONG_MAGIC_NUMBER;
+  /* Check that EDID structure revision 1.3 is used, it is the only version
+     we support. It is also by far the most commonly use revision and it is
+     currently the newest revision. */
   else if (__test_version(this->edid, 1, 3) == 0)
     error = LIBGAMMA_EDID_REVISION_UNSUPPORTED;
   
+  /* If we have encountered an error, report it for the fields that require
+     the EDID to be parsed. Note that it is not stored for the EDID field
+     itself because it is not considered an error just because we do not
+     support the used version. */
   this->width_mm_edid_error = this->height_mm_edid_error = this->gamma_error = error;
   
+  /* Retrieve the size of the viewport. This is done even if it is not
+     requested because it is not worth it branch. */
   this->width_mm_edid = (size_t)(this->edid[21]) * 10;
   this->height_mm_edid = (size_t)(this->edid[22]) * 10;
   
+  /* Retrieve the monitor's gamma characteristics. */
   if ((fields & LIBGAMMA_CRTC_INFO_GAMMA) && (error == 0))
     {
       if (this->edid[23] == 0xFF)
+	/* If the gamma charactistics is FFh (3,55) it should be interpreted as not specified. */
 	this->gamma_error = LIBGAMMA_GAMMA_NOT_SPECIFIED;
       else
 	this->gamma_red = this->gamma_green = this->gamma_blue = (float)((int)(this->edid[23]) + 100) / 100.f;
     }
   
+  /* If not error has occurred, calculate and test the checksum.
+     It is not considered an error that the gamma characteristics
+     is left unspecified in the EDID. */
   if (error == 0)
     for (i = 0; i < this->edid_length; i++)
       checksum += (int)(this->edid[i]);
+  /* The checksum should be zero. */
   if ((checksum & 255))
     {
+      /* Store the error in all fields that require the EDID to be parsed,
+         as well as the EDID field itself. */
       error = LIBGAMMA_EDID_CHECKSUM_ERROR;
       this->edid_error = this->width_mm_edid_error = this->height_mm_edid_error = error;
+      /* If the gamma characteristics is not specified, that is kept,
+         and the checksum error is augmented. */
       this->gamma_error = this->gamma_error == LIBGAMMA_GAMMA_NOT_SPECIFIED
-	? LIBGAMMA_GAMMA_NOT_SPECIFIED_AND_EDID_CHECKSUM_ERROR : 0;
+	? LIBGAMMA_GAMMA_NOT_SPECIFIED_AND_EDID_CHECKSUM_ERROR : error;
     }
   
+  /* Return whether or not we encountered an error or if
+     the gamma characteristics was requested but is not
+     specified in the monitor's EDID. */
   return error | this->gamma_error;
   
+#undef __m
 #undef __test_version
 }
 
diff --git a/src/lib/gamma-helper.c b/src/lib/gamma-helper.c
index dd4e027..5e3c09b 100644
--- a/src/lib/gamma-helper.c
+++ b/src/lib/gamma-helper.c
@@ -25,9 +25,15 @@
 #include <stdint.h>
 
 
+/**
+ * Just an arbitrary version
+ */
 #define ANY  bits64
 
 
+#define __translate(instruction)  for (i = 0; i < n; i++)  instruction;  break
+
+
 /**
  * Convert any set of gamma ramps into a 64-bit integer array with all channels.
  * 
@@ -41,32 +47,16 @@ static void translate_to_64(signed depth, size_t n, uint64_t* restrict out, libg
   size_t i;
   switch (depth)
     {
-    case 16:
-      for (i = 0; i < n; i++)
-	out[i] = (uint64_t)(in.bits16.red[i]) * 0x0001000100010001ULL;
-      break;
-      
-    case 32:
-      for (i = 0; i < n; i++)
-	out[i] = (uint64_t)(in.bits32.red[i]) * 0x0000000100000001ULL;
-      break;
-      
-    case 64:
-      for (i = 0; i < n; i++)
-	out[i] = in.bits64.red[i];
-      break;
-      
-    case -1:
-      for (i = 0; i < n; i++)
-	out[i] = (uint64_t)(in.float_single.red[i] * (float)UINT64_MAX);
-      break;
-      
-    case -2:
-      for (i = 0; i < n; i++)
-	out[i] = (uint64_t)(in.float_double.red[i] * (double)UINT64_MAX);
-      break;
-      
-    default: /* This is not possible. */
+      /* Translate integer. */
+    case 16:  __translate(out[i] = (uint64_t)(in.bits16.red[i]) * 0x0001000100010001ULL);
+    case 32:  __translate(out[i] = (uint64_t)(in.bits32.red[i]) * 0x0000000100000001ULL);
+      /* Identity translation. */
+    case 64:  __translate(out[i] = in.bits64.red[i]);
+      /* Translate floating point. */
+    case -1:  __translate(out[i] = (uint64_t)(in.float_single.red[i] * (float)UINT64_MAX));
+    case -2:  __translate(out[i] = (uint64_t)(in.float_double.red[i] * (double)UINT64_MAX));
+    default:
+      /* This is not possible. */
       abort();
       break;
     }
@@ -84,35 +74,18 @@ static void translate_to_64(signed depth, size_t n, uint64_t* restrict out, libg
 static void translate_from_64(signed depth, size_t n, libgamma_gamma_ramps_any_t out, uint64_t* restrict in)
 {
   size_t i;
-  
   switch (depth)
     {
-    case 16:
-      for (i = 0; i < n; i++)
-	out.bits16.red[i] = (uint16_t)(in[i] / 0x0001000100010001ULL);
-      break;
-      
-    case 32:
-      for (i = 0; i < n; i++)
-	out.bits32.red[i] = (uint32_t)(in[i] / 0x0000000100000001ULL);
-      break;
-      
-    case 64:
-      for (i = 0; i < n; i++)
-	out.bits64.red[i] = in[i];
-      break;
-      
-    case -1:
-      for (i = 0; i < n; i++)
-	out.float_single.red[i] = (float)(in[i]) / (float)UINT64_MAX;
-      break;
-      
-    case -2:
-      for (i = 0; i < n; i++)
-	out.float_double.red[i] = (double)(in[i]) / (double)UINT64_MAX;
-      break;
-      
-    default: /* This is not possible. */
+      /* Translate integer. */
+    case 16:  __translate(out.bits16.red[i] = (uint16_t)(in[i] / 0x0001000100010001ULL));
+    case 32:  __translate(out.bits32.red[i] = (uint32_t)(in[i] / 0x0000000100000001ULL));
+      /* Identity translation. */
+    case 64:  __translate(out.bits64.red[i] = in[i]);
+      /* Translate floating point. */
+    case -1:  __translate(out.float_single.red[i] = (float)(in[i]) / (float)UINT64_MAX);
+    case -2:  __translate(out.float_double.red[i] = (double)(in[i]) / (double)UINT64_MAX);
+    default:
+      /* This is not possible. */
       abort();
       break;
     }
@@ -133,8 +106,7 @@ static void translate_from_64(signed depth, size_t n, libgamma_gamma_ramps_any_t
 static int allocated_any_ramp(libgamma_gamma_ramps_any_t* restrict ramps_sys,
 			      libgamma_gamma_ramps_any_t ramps, signed depth, size_t* restrict elements)
 {
-  size_t n = 0;
-  size_t d;
+  size_t n = 0, d;
   
   switch (depth)
     {
@@ -156,7 +128,7 @@ static int allocated_any_ramp(libgamma_gamma_ramps_any_t* restrict ramps_sys,
   ramps_sys->ANY.blue  = (void*)(((char*)(ramps_sys->ANY.green)) + ramps.ANY.green_size * d / sizeof(char));
   
   *elements = n;
-  return ramps_sys->ANY.red ? 0 : LIBGAMMA_ERRNO_SET;
+  return ramps_sys->ANY.red == NULL ? LIBGAMMA_ERRNO_SET : 0;
 }
 
 
@@ -189,16 +161,10 @@ int libgamma_translated_ramp_get_(libgamma_crtc_state_t* restrict this,
     return r;
   
   if ((r = fun(this, &ramps_sys)))
-    {
-      free(ramps_sys.ANY.red);
-      return r;
-    }
+    return free(ramps_sys.ANY.red), r;
   
   if ((ramps_full = malloc(n * sizeof(uint64_t))) == NULL)
-    {
-      free(ramps_sys.ANY.red);
-      return LIBGAMMA_ERRNO_SET;
-    }
+    return free(ramps_sys.ANY.red), LIBGAMMA_ERRNO_SET;
   
   translate_to_64(depth_system, n, ramps_full, ramps_sys);
   free(ramps_sys.ANY.red);
@@ -238,10 +204,7 @@ int libgamma_translated_ramp_set_(libgamma_crtc_state_t* restrict this,
     return r;
   
   if ((ramps_full = malloc(n * sizeof(uint64_t))) == NULL)
-    {
-      free(ramps_sys.ANY.red);
-      return LIBGAMMA_ERRNO_SET;
-    }
+    return free(ramps_sys.ANY.red), LIBGAMMA_ERRNO_SET;
   
   translate_to_64(depth_user, n, ramps_full, ramps);
   translate_from_64(depth_system, n, ramps_sys, ramps_full);
@@ -254,5 +217,6 @@ int libgamma_translated_ramp_set_(libgamma_crtc_state_t* restrict this,
 }
 
 
+#undef __translate
 #undef ANY
 
diff --git a/src/lib/libgamma-error.c.gpp b/src/lib/libgamma-error.c.gpp
index d443f74..64f1904 100644
--- a/src/lib/libgamma-error.c.gpp
+++ b/src/lib/libgamma-error.c.gpp
@@ -34,13 +34,16 @@
 
 
 /**
- * Group that the user needs to be a member of if `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned.
+ * Group that the user needs to be a member of if
+ * `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned.
  */
 gid_t libgamma_group_gid = 0;
 
 /**
- * Group that the user needs to be a member of if `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned,
- * `NULL` if the name of the group `libgamma_group_gid` cannot be determined.
+ * Group that the user needs to be a member of if
+ * `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned,
+ * `NULL` if the name of the group `libgamma_group_gid`
+ * cannot be determined.
  */
 const char* libgamma_group_name = NULL;
 
@@ -67,23 +70,30 @@ void libgamma_perror(const char* name, int error_code)
 {
   if (error_code >= 0)
     {
+      /* Print the stored errno value. */
       errno = error_code;
       perror(name);
     }
   else if (error_code == LIBGAMMA_ERRNO_SET)
+    /* Print errno. */
     perror(name);
   else if (error_code == LIBGAMMA_DEVICE_REQUIRE_GROUP)
     {
+      /* Print the error name and the required group membership. */
       const char* error = libgamma_name_of_error(error_code);
       long int gid = (long int)libgamma_group_gid;
       if (libgamma_group_name == NULL)
+	/* Group name unknown. */
 	fprintf(stderr, "%s: %s: %ld\n", name, error, gid);
       else
-	fprintf(stderr, "%s: %s: %s (%lid)\n", name, error, libgamma_group_name, gid);
+	/* Group name known, ID is second class. */
+	fprintf(stderr, "%s: %s: %s (%ld)\n", name, error, libgamma_group_name, gid);
     }
   else if (error_code < LIBGAMMA_ERROR_MIN)
+    /* If the error code does not exist, print "(?)" */
     fprintf(stderr, "%s: (?)\n", name);
   else
+    /* Print the name of the error. */
     fprintf(stderr, "%s: %s\n", name, libgamma_name_of_error(error_code));
 }
 
@@ -98,6 +108,9 @@ void libgamma_perror(const char* name, int error_code)
  */
 const char* libgamma_name_of_error(int value)
 {
+  /* Map from error codes to error names.
+     The output of $(libgamma-error-extract --list)
+     is sorted by error code in decreasing order. */
   static const char* error_names[] =
     {
 £>for error in $(libgamma-error-extract --list); do
@@ -105,9 +118,12 @@ const char* libgamma_name_of_error(int value)
 £>done
     };
   
+  /* Return `NULL` if the error code is invalid. */
   if ((value < LIBGAMMA_ERROR_MIN) || (value >= 0))
     return NULL;
   
+  /* Convert error code from {-1, -2, -3, ...} to {0, 1, 2, ...}
+     and look up the error's name and return it. */
   return error_names[-value - 1];
 }
 
@@ -121,13 +137,16 @@ const char* libgamma_name_of_error(int value)
  */
 int libgamma_value_of_error(const char* name)
 {
+  /* Return 0 (not a valid error code) if the error name is `NULL`. */
   if (name == NULL)
     return 0;
   
+  /* Test error names against `name` and return the value of the match error. */
 £>for error in $(libgamma-error-extract --list); do
   if (!strcmp(name, "£{error}"))  return £{error};
 £>done
   
+  /* Return 0 (not a valid error code) if the error name is unknown. */
   return 0;
 }
 
diff --git a/src/lib/libgamma-error.h b/src/lib/libgamma-error.h
index 06a7077..8431877 100644
--- a/src/lib/libgamma-error.h
+++ b/src/lib/libgamma-error.h
@@ -26,13 +26,16 @@
 
 
 /**
- * Group that the user needs to be a member of if `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned.
+ * Group that the user needs to be a member of if
+ * `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned.
  */
 extern gid_t libgamma_group_gid;
 
 /**
- * Group that the user needs to be a member of if `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned,
- * `NULL` if the name of the group `libgamma_group_gid` cannot be determined.
+ * Group that the user needs to be a member of if
+ * `LIBGAMMA_DEVICE_REQUIRE_GROUP` is returned,
+ * `NULL` if the name of the group `libgamma_group_gid`
+ * cannot be determined.
  */
 extern const char* libgamma_group_name;
 
@@ -65,80 +68,95 @@ extern const char* libgamma_group_name;
 #define LIBGAMMA_NO_SUCH_CRTC  (-5)
 
 /**
- * Counter overflowed when counting the number of available items.
+ * Counter overflowed when counting the number
+ * of available items.
  */
 #define LIBGAMMA_IMPOSSIBLE_AMOUNT  (-6)
 
 /**
- * The selected connector is disabled, it does not have a CRTC.
+ * The selected connector is disabled, it does
+ * not have a CRTC.
  */
 #define LIBGAMMA_CONNECTOR_DISABLED  (-7)
 
 /**
- * The selected CRTC could not be opened, reason unknown.
+ * The selected CRTC could not be opened,
+ * reason unknown.
  */
 #define LIBGAMMA_OPEN_CRTC_FAILED  (-8)
 
 /**
- * The CRTC information field is not supported by the adjustment method.
+ * The CRTC information field is not supported
+ * by the adjustment method.
  */
 #define LIBGAMMA_CRTC_INFO_NOT_SUPPORTED  (-9)
 
 /**
- * Failed to read the current gamma ramps for the selected CRTC, reason unknown.
+ * Failed to read the current gamma ramps for
+ * the selected CRTC, reason unknown.
  */
 #define LIBGAMMA_GAMMA_RAMP_READ_FAILED  (-10)
 
 /**
- * Failed to write the current gamma ramps for the selected CRTC, reason unknown.
+ * Failed to write the current gamma ramps for
+ * the selected CRTC, reason unknown.
  */
 #define LIBGAMMA_GAMMA_RAMP_WRITE_FAILED  (-11)
 
 /**
- * The specified ramp sizes does not match the ramps sizes returned by the
- * adjustment methods in response to the query/command.
+ * The specified ramp sizes does not match the
+ * ramps sizes returned by the adjustment methods
+ * in response to the query/command.
  */
 #define LIBGAMMA_GAMMA_RAMP_SIZE_CHANGED  (-12)
 
 /**
- * The specified ramp sizes are not identical which is required by the adjustment method.
+ * The specified ramp sizes are not identical
+ * which is required by the adjustment method.
  * (Only returned in debug mode.)
  */
 #define LIBGAMMA_MIXED_GAMMA_RAMP_SIZE  (-13)
 
 /**
- * The specified ramp sizes are not supported by the adjustment method.
+ * The specified ramp sizes are not supported
+ * by the adjustment method.
  * (Only returned in debug mode.)
  */
 #define LIBGAMMA_WRONG_GAMMA_RAMP_SIZE  (-14)
 
 /**
- * The adjustment method reported that the gamma ramps size is 1, or perhaps even zero or negative.
+ * The adjustment method reported that the gamma
+ * ramps size is 1, or perhaps even zero or negative.
  */
 #define LIBGAMMA_SINGLETON_GAMMA_RAMP  (-15)
 
 /**
- * The adjustment method failed to list available CRTC:s, reason unknown.
+ * The adjustment method failed to list
+ * available CRTC:s, reason unknown.
  */
 #define LIBGAMMA_LIST_CRTCS_FAILED  (-16)
 
 /**
- * Failed to acquire mode resources from the adjustment method.
+ * Failed to acquire mode resources from the
+ * adjustment method.
  */
 #define LIBGAMMA_ACQUIRING_MODE_RESOURCES_FAILED  (-17)
 
 /**
- * The adjustment method reported that a negative number of partitions exists in the site.
+ * The adjustment method reported that a negative
+ * number of partitions exists in the site.
  */
 #define LIBGAMMA_NEGATIVE_PARTITION_COUNT  (-18)
 
 /**
- * The adjustment method reported that a negative number of CRTC:s exists in the partition.
+ * The adjustment method reported that a negative
+ * number of CRTC:s exists in the partition.
  */
 #define LIBGAMMA_NEGATIVE_CRTC_COUNT  (-19)
 
 /**
- * Device cannot be access becauses of insufficient permissions.
+ * Device cannot be access becauses of
+ * insufficient permissions.
  */
 #define LIBGAMMA_DEVICE_RESTRICTED  (-20)
 
@@ -148,9 +166,10 @@ extern const char* libgamma_group_name;
 #define LIBGAMMA_DEVICE_ACCESS_FAILED  (-21)
 
 /**
- * Device cannot be access, membership of the `libgamma_group_gid`
- * (named by `libgamma_group_name` (can be `NULL`, if so `errno` may
- * have been set to tell why)) is required.
+ * Device cannot be access, membership of the
+ * `libgamma_group_gid` (named by `libgamma_group_name`
+ * (can be `NULL`, if so `errno` may have been set
+ * to tell why)) is required.
  */
 #define LIBGAMMA_DEVICE_REQUIRE_GROUP  (-22)
 
@@ -165,95 +184,112 @@ extern const char* libgamma_group_name;
 #define LIBGAMMA_STATE_UNKNOWN  (-24)
 
 /**
- * Failed to determine which connector the CRTC belongs to.
+ * Failed to determine which connector the
+ * CRTC belongs to.
  */
 #define LIBGAMMA_CONNECTOR_UNKNOWN  (-25)
 
 /**
- * The detected connector type is not listed in this library and has to be updated.
+ * The detected connector type is not listed
+ * in this library and has to be updated.
  */
 #define LIBGAMMA_CONNECTOR_TYPE_NOT_RECOGNISED  (-26)
 
 /**
- * The detected subpixel order is not listed in this library and has to be updated.
+ * The detected subpixel order is not listed
+ * in this library and has to be updated.
  */
 #define LIBGAMMA_SUBPIXEL_ORDER_NOT_RECOGNISED  (-27)
 
 /**
- * The length of the EDID does not match that of any supported EDID structure revision.
+ * The length of the EDID does not match that
+ * of any supported EDID structure revision.
  */
 #define LIBGAMMA_EDID_LENGTH_UNSUPPORTED  (-28)
 
 /**
- * The magic number in the EDID does not match that of any supported EDID structure revision.
+ * The magic number in the EDID does not match
+ * that of any supported EDID structure revision.
  */
 #define LIBGAMMA_EDID_WRONG_MAGIC_NUMBER  (-29)
 
 /**
- * The EDID structure revision used by the monitor is not supported.
+ * The EDID structure revision used by the
+ * monitor is not supported.
  */
 #define LIBGAMMA_EDID_REVISION_UNSUPPORTED  (-30)
 
 /**
- * The gamma characteristics field in the EDID is left unspecified.
+ * The gamma characteristics field in the EDID
+ * is left unspecified.
  * (This could be considered a non-error.)
  */
 #define LIBGAMMA_GAMMA_NOT_SPECIFIED  (-31)
 
 /**
- * The checksum in the EDID is incorrect, all request information has been provided
+ * The checksum in the EDID is incorrect, all
+ * request information has been provided
  * by you cannot count on it.
  */
 #define LIBGAMMA_EDID_CHECKSUM_ERROR  (-32)
 
 /**
- * Both of the errors `LIBGAMMA_GAMMA_NOT_SPECIFIED` and
- * `LIBGAMMA_EDID_CHECKSUM_ERROR` have occurred.
+ * Both of the errors `LIBGAMMA_GAMMA_NOT_SPECIFIED`
+ * and `LIBGAMMA_EDID_CHECKSUM_ERROR` have occurred.
  */
 #define LIBGAMMA_GAMMA_NOT_SPECIFIED_AND_EDID_CHECKSUM_ERROR  (-33)
 
 /**
- * Failed to query the gamma ramps size from the adjustment method, reason unknown.
+ * Failed to query the gamma ramps size from the
+ * adjustment method, reason unknown.
  */
 #define LIBGAMMA_GAMMA_RAMPS_SIZE_QUERY_FAILED  (-34)
 
 /**
- * The selected partition could not be opened, reason unknown.
+ * The selected partition could not be opened,
+ * reason unknown.
  */
 #define LIBGAMMA_OPEN_PARTITION_FAILED  (-35)
 
 /**
- * The selected site could not be opened, reason unknown.
+ * The selected site could not be opened,
+ * reason unknown.
  */
 #define LIBGAMMA_OPEN_SITE_FAILED  (-36)
 
 /**
- * Failed to query the adjustment method for its protocol version, reason unknown.
+ * Failed to query the adjustment method for
+ * its protocol version, reason unknown.
  */
 #define LIBGAMMA_PROTOCOL_VERSION_QUERY_FAILED  (-37)
 
 /**
- * The adjustment method's version of its protocol is not supported.
+ * The adjustment method's version of its
+ * protocol is not supported.
  */
 #define LIBGAMMA_PROTOCOL_VERSION_NOT_SUPPORTED  (-38)
 
 /**
- * The adjustment method failed to list available partitions, reason unknown.
+ * The adjustment method failed to list
+ * available partitions, reason unknown.
  */
 #define LIBGAMMA_LIST_PARTITIONS_FAILED  (-39)
 
 /**
- * Partition exists by index, but the partition at that index does not exist.
+ * Partition exists by index, but the partition
+ * at that index does not exist.
  */
 #define LIBGAMMA_NULL_PARTITION  (-40)
 
 /**
- * There is not monitor connected to the connector of the selected CRTC.
+ * There is not monitor connected to the
+ * connector of the selected CRTC.
  */
 #define LIBGAMMA_NOT_CONNECTED  (-41)
 
 /**
- * Data extraction from a reply from the adjustment method failed, reason unknown.
+ * Data extraction from a reply from the
+ * adjustment method failed, reason unknown.
  */
 #define LIBGAMMA_REPLY_VALUE_EXTRACTION_FAILED  (-42)
 
@@ -263,26 +299,30 @@ extern const char* libgamma_group_name;
 #define LIBGAMMA_EDID_NOT_FOUND  (-43)
 
 /**
- * Failed to list properties on the output, reason unknown.
+ * Failed to list properties on the output,
+ * reason unknown.
  */
 #define LIBGAMMA_LIST_PROPERTIES_FAILED  (-44)
 
 /**
- * Failed to query a property's value from the output, reason unknown.
+ * Failed to query a property's value from
+ * the output, reason unknown.
  */
 #define LIBGAMMA_PROPERTY_VALUE_QUERY_FAILED  (-45)
 
 /**
- * A request for information on an output failed, reason unknown.
+ * A request for information on an output
+ * failed, reason unknown.
  */
 #define LIBGAMMA_OUTPUT_INFORMATION_QUERY_FAILED  (-46)
 
 
 
 /**
- * The number of the libgamma error with the lowest number.
- * If this is lower than the number your program thinks it
- * should be sould update your program for new errors.
+ * The number of the libgamma error with the
+ * lowest number. If this is lower than the
+ * number your program thinks it should be sould
+ * update your program for new errors.
  */
 #define LIBGAMMA_ERROR_MIN  (-46)
 
diff --git a/src/lib/libgamma-method.c b/src/lib/libgamma-method.c
index 4c81549..f9fa7a3 100644
--- a/src/lib/libgamma-method.c
+++ b/src/lib/libgamma-method.c
@@ -40,7 +40,7 @@ int libgamma_gamma_ramps_initialise(libgamma_gamma_ramps_t* restrict this)
   this->red   = malloc(n * sizeof(uint16_t));
   this->green = this->  red + this->  red_size;
   this->blue  = this->green + this->green_size;
-  return this->red ? 0 : -1;
+  return this->red == NULL ? -1 : 0;
 }
 
 
@@ -89,7 +89,7 @@ int libgamma_gamma_ramps32_initialise(libgamma_gamma_ramps32_t* restrict this)
   this->red   = malloc(n * sizeof(uint32_t));
   this->green = this->  red + this->  red_size;
   this->blue  = this->green + this->green_size;
-  return this->red ? 0 : -1;
+  return this->red == NULL ? -1 : 0;
 }
 
 
@@ -138,7 +138,7 @@ int libgamma_gamma_ramps64_initialise(libgamma_gamma_ramps64_t* restrict this)
   this->red   = malloc(n * sizeof(uint64_t));
   this->green = this->  red + this->  red_size;
   this->blue  = this->green + this->green_size;
-  return this->red ? 0 : -1;
+  return this->red == NULL ? -1 : 0;
 }
 
 
@@ -187,7 +187,7 @@ int libgamma_gamma_rampsf_initialise(libgamma_gamma_rampsf_t* restrict this)
   this->red   = malloc(n * sizeof(float));
   this->green = this->  red + this->  red_size;
   this->blue  = this->green + this->green_size;
-  return this->red ? 0 : -1;
+  return this->red == NULL ? -1 : 0;
 }