Refactoring and code style improvementsHEADmaster

Signed-off-by: Joseph Elliott Hand <jhand@hawaii.edu>

2 files changed, 98 insertions, 111 deletions

diff --git a/.clang-format b/.clang-format
index 55bb745..61a3de0 100644
--- a/.clang-format
+++ b/.clang-format
@@ -8,6 +8,7 @@ AlignConsecutiveAssignments:
   Enabled: true
 AlignConsecutiveDeclarations:
   Enabled: true
+AlignArrayOfStructures: Left
 
 AlwaysBreakAfterDefinitionReturnType: All
 
diff --git a/unit.h b/unit.h
index 32a26c0..997852d 100644
--- a/unit.h
+++ b/unit.h
@@ -1,29 +1,29 @@
 /*
  * unit.h - Small library for handling dimensioned quantities in C.
  * Copyright (C) 2026 Joseph Hand
- * 
+ *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or
  * (at your option) any later version.
- * 
+ *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
- 
+
 #ifndef _UNITH
 #define _UNITH
 
-#define U(str) get_unit_value(str)
+#define U(str) unith_parse_compound_unit(str)
 #define UFMT "%.3e %s"
-#define UARG(value, units) ((value) / get_unit_value(units)), (units)
+#define UARG(value, units) ((value) / unith_parse_compound_unit(units)), (units)
 
-double get_unit_value(char const * string);
+double unith_parse_compound_unit(char const * string);
 
 #ifdef UNITH_IMPL
 
@@ -33,76 +33,12 @@ double get_unit_value(char const * string);
 #include <stdlib.h>
 #include <string.h>
 
+#define LEN(a) ((int)(sizeof(a) / sizeof((a)[0])))
+
 typedef struct {
 	char   abbr[8];
 	double value;
-} Unit;
-
-double unit_prefixes[255] = {
-	['Q'] = 1e30,
-	['R'] = 1e27,
-	['Y'] = 1e24,
-	['Z'] = 1e21,
-	['E'] = 1e18,
-	['P'] = 1e15,
-	['T'] = 1e12,
-	['G'] = 1e9,
-	['M'] = 1e6,
-	['k'] = 1e3,
-	['h'] = 1e2,
-	['d'] = 1e-1,
-	['c'] = 1e-2,
-	['m'] = 1e-3,
-	['u'] = 1e-6,
-	['n'] = 1e-9,
-	['p'] = 1e-12,
-	['f'] = 1e-15,
-	['a'] = 1e-18,
-	['z'] = 1e-21,
-	['y'] = 1e-24,
-	['r'] = 1e-27,
-	['q'] = 1e-30
-};
-
-Unit units[] = {
-
-    {"rad", 1},
-    {"deg", 0.01745329252},
-    {"arcmin", 0.0002908882087},
-    {"arcsec", 0.000004848136811},
-
-    {"sr", 1.0},
-
-    {"s", 1.0},
-    {"m", 1.0},
-    {"g", 0.001},
-    {"A", 1.0},
-    {"K", 1.0},
-    {"Hz", 1.0},
-    {"N", 1.0},
-    {"Pa", 1.0},
-    {"J", 1.0},
-    {"W", 1.0},
-    {"C", 1.0},
-    {"V", 1.0},
-    {"Wb", 1.0},
-    {"T", 1.0},
-    {"F", 1.0},
-    {"Ohm", 1.0},
-    {"S", 1.0},
-    {"H", 1.0},
-
-    {"Jy", 1e-27},
-    {"AU", 1.495978707e11},
-    {"pc", 3.0857e16},
-
-    {"Msun", 1.99e30},
-    {"Mearth", 5.9722e24},
-    {"Mjup", 1.89813e27},
-
-    {"Rsun", 6.957e8},
-    {"Rearth", 6.371e6},
-    {"Rjup", 7.1492e7}};
+} unith_Unit;
 
 typedef struct {
 	enum { SPACE, ONE, SLASH, EXP, NAME, NUMBER } type;
@@ -110,10 +46,61 @@ typedef struct {
 		char   str[8];
 		double num;
 	} value;
-} Token;
+} unith_Token;
+
+int    unith_get_token(char const * str, unith_Token * token);
+double unith_parse_unit(char const * name);
+double unith_parse_compound_unit(char const * string);
+
+double unith_prefixes[255] = {
+    ['Q'] = 1e30,  ['R'] = 1e27,  ['Y'] = 1e24,  ['Z'] = 1e21,  ['E'] = 1e18,
+    ['P'] = 1e15,  ['T'] = 1e12,  ['G'] = 1e9,   ['M'] = 1e6,   ['k'] = 1e3,
+    ['h'] = 1e2,   ['d'] = 1e-1,  ['c'] = 1e-2,  ['m'] = 1e-3,  ['u'] = 1e-6,
+    ['n'] = 1e-9,  ['p'] = 1e-12, ['f'] = 1e-15, ['a'] = 1e-18, ['z'] = 1e-21,
+    ['y'] = 1e-24, ['r'] = 1e-27, ['q'] = 1e-30};
+
+unith_Unit unith_units[] = {
+    {"rad",    1                },
+    {"deg",    0.01745329252    },
+    {"arcmin", 0.0002908882087  },
+    {"arcsec", 0.000004848136811},
+
+    {"sr",     1.0              },
+
+    {"s",      1.0              },
+    {"m",      1.0              },
+    {"g",      0.001            },
+    {"A",      1.0              },
+    {"K",      1.0              },
+    {"Hz",     1.0              },
+    {"N",      1.0              },
+    {"Pa",     1.0              },
+    {"J",      1.0              },
+    {"W",      1.0              },
+    {"C",      1.0              },
+    {"V",      1.0              },
+    {"Wb",     1.0              },
+    {"T",      1.0              },
+    {"F",      1.0              },
+    {"Ohm",    1.0              },
+    {"S",      1.0              },
+    {"H",      1.0              },
+
+    {"Jy",     1e-27            },
+    {"AU",     1.495978707e11   },
+    {"pc",     3.0857e16        },
+
+    {"Msun",   1.99e30          },
+    {"Mearth", 5.9722e24        },
+    {"Mjup",   1.89813e27       },
+
+    {"Rsun",   6.957e8          },
+    {"Rearth", 6.371e6          },
+    {"Rjup",   7.1492e7         }
+};
 
 int
-get_token(char const * str, Token * token) {
+unith_get_token(char const * str, unith_Token * token) {
 
 	int len = 0;
 
@@ -127,7 +114,7 @@ get_token(char const * str, Token * token) {
 		return len;
 	}
 
-	if (str[0] == 1 && (str[1] < '0' || str[1] > '9') && str[1] != '.') {
+	if (str[0] == '1' && (str[1] < '0' || str[1] > '9') && str[1] != '.') {
 		token->type = ONE;
 		return 1;
 	}
@@ -169,34 +156,35 @@ get_token(char const * str, Token * token) {
 }
 
 double
-resolve_unit_name(char const * name) {
-	
-	double prefix_amount = unit_prefixes[name[0]];
-	if(prefix_amount > 0) {
-		for (int j = 0; j < sizeof(units) / sizeof(units[0]); j++) {
-			if (strcmp(&name[1], units[j].abbr)) continue;
-			return prefix_amount * units[j].value;
+unith_parse_unit(char const * name) {
+
+	double prefix_amount = unith_prefixes[(unsigned int)name[0]];
+	if (prefix_amount > 0) {
+		for (int j = 0; j < LEN(unith_units); j++) {
+			if (strcmp(&name[1], unith_units[j].abbr)) continue;
+			return prefix_amount * unith_units[j].value;
 		}
 	}
 
-	for (int j = 0; j < sizeof(units) / sizeof(units[0]); j++) {
-		if (strcmp(name, units[j].abbr)) continue;
-		return units[j].value;
+	for (int j = 0; j < LEN(unith_units); j++) {
+		if (strcmp(name, unith_units[j].abbr)) continue;
+		return unith_units[j].value;
 	}
-	
+
 	return 0.0;
 }
 
 double
-get_unit_value(char const * string) {
+unith_parse_compound_unit(char const * string) {
 
-	int   offset      = 0;
-	int   token_count = 0;
-	Token tokens[32];
+	int         offset      = 0;
+	int         token_count = 0;
+	unith_Token tokens[32];
 
 	for (;;) {
 
-		int result = get_token(string + offset, &tokens[token_count]);
+		int result =
+		    unith_get_token(string + offset, &tokens[token_count]);
 
 		if (result < 0) {
 			goto error;
@@ -215,37 +203,35 @@ get_unit_value(char const * string) {
 
 	for (; i < token_count;) {
 		if (tokens[i].type == ONE) {
-			if (i == 0 && token_count > 1 && tokens[1].type == SLASH) {
-				exp_sign = -1.0;
-				i += 2;
-				continue;
-			} else {
-				goto error;
-			}
+			if (i > 0) goto error;
+			if (token_count <= 1) goto error;
+			if (tokens[1].type != SLASH) goto error;
+
+			exp_sign = -1.0;
+			i += 2;
+			continue;
 		}
 
 		if (tokens[i].type == SLASH) {
-			if (exp_sign > 0) {
-				exp_sign = -1.0;
-				i += 1;
-				continue;
-			} else {
-				goto error;
-			}
+			if (exp_sign < 0) goto error;
+			exp_sign = -1.0;
+			i += 1;
+			continue;
 		}
 
 		if (tokens[i].type != NAME) goto error;
 
-		double unit_value = resolve_unit_name(tokens[i].value.str);
-		if(unit_value == 0.0) goto error;
+		double unit_value = unith_parse_unit(tokens[i].value.str);
+		if (unit_value == 0.0) goto error;
 
-		if (token_count <= i+1 || tokens[i + 1].type != EXP) {
+		if (token_count <= i + 1 || tokens[i + 1].type != EXP) {
 			value *= pow(unit_value, exp_sign);
 			i += 1;
 			continue;
 		}
 
-		if (token_count <= i+2 || tokens[i + 2].type != NUMBER) goto error;
+		if (token_count <= i + 2 || tokens[i + 2].type != NUMBER)
+			goto error;
 
 		value *= pow(unit_value, exp_sign * tokens[i + 2].value.num);
 		i += 3;