Add trim and trim_empty support to strsplit and update all callers

cmdline/state.c

@@ -837,7 +837,7 @@ void state_config(struct snapraid_state* state, const char* path, const char* co
 				/* LCOV_EXCL_STOP */
 			}
 
-			split_mac = strsplit(split_map, SPLIT_MAX + 1, buffer, ",");
+			split_mac = strsplit(split_map, SPLIT_MAX + 1, buffer, ",", " \t\r\n", 0);
 
 			if (split_mac > SPLIT_MAX) {
 				/* LCOV_EXCL_START */

cmdline/str.c

@@ -22,27 +22,74 @@ char* strpolish(char* s)
 	return s;
 }
 
-unsigned strsplit(char** split_map, unsigned split_max, char* str, const char* delimiters)
+unsigned strsplit(char** split_map, unsigned split_max, char* str, const char* delimiters, const char* trim, int trim_empty)
 {
 	unsigned mac = 0;
 
-	/* skip initial delimiters */
-	str += strspn(str, delimiters);
-
-	while (*str != 0 && mac < split_max) {
-		/* start of the token */
-		split_map[mac] = str;
-		++mac;
-
-		/* find the first delimiter or the end of the string */
-		str += strcspn(str, delimiters);
-
-		/* put the final terminator if missing */
-		if (*str != 0)
-			*str++ = 0;
-
-		/* skip trailing delimiters */
+	if (trim_empty) {
+		/* skip initial delimiters */
 		str += strspn(str, delimiters);
+
+		while (*str != 0 && mac < split_max) {
+			/* start of the token */
+			char* tok_start = str;
+
+			/* find the first delimiter or the end of the string */
+			str += strcspn(str, delimiters);
+
+			/* put the final terminator if missing */
+			if (*str != 0)
+				*str++ = 0;
+
+			/* skip trailing delimiters */
+			str += strspn(str, delimiters);
+
+			/* trim the token if trim is specified */
+			if (trim != 0) {
+				tok_start += strspn(tok_start, trim);
+				size_t len = strlen(tok_start);
+				while (len > 0 && strchr(trim, tok_start[len - 1]) != 0) {
+					tok_start[len - 1] = 0;
+					--len;
+				}
+			}
+
+			/* store the token only if it's not empty */
+			if (*tok_start != 0) {
+				split_map[mac] = tok_start;
+				++mac;
+			}
+		}
+	} else {
+		if (*str == 0)
+			return 0;
+
+		while (mac < split_max) {
+			char* tok_start = str;
+
+			str += strcspn(str, delimiters);
+
+			int has_next = *str != 0;
+			if (has_next) {
+				*str = 0;
+				++str;
+			}
+
+			if (trim != 0) {
+				tok_start += strspn(tok_start, trim);
+				size_t len = strlen(tok_start);
+				while (len > 0 && strchr(trim, tok_start[len - 1]) != 0) {
+					tok_start[len - 1] = 0;
+					--len;
+				}
+			}
+
+			split_map[mac] = tok_start;
+			++mac;
+
+			if (!has_next)
+				break;
+		}
 	}
 
 	return mac;

cmdline/str.h

@@ -26,8 +26,9 @@ char* strpolish(char* s);
  * null-terminates each token by overwriting its trailing delimiter,
  * and stores a pointer to each token's start in @split_map.
  *
- * Leading and consecutive delimiters are silently skipped, so the
- * output never contains empty tokens.
+ * If @trim_empty is non-zero, leading and consecutive delimiters are
+ * silently skipped, and tokens trimmed to empty are discarded.
+ * If @trim_empty is zero, empty tokens are preserved.
  *
  * The input string is modified in-place; @split_map entries point
  * directly into @str and are only valid for its lifetime.
@@ -36,15 +37,17 @@ char* strpolish(char* s);
  * \param split_max Capacity of @split_map; at most this many tokens are stored.
  * \param str Input string to tokenise (modified in-place).
  * \param delimiters Null-terminated set of delimiter characters.
+ * \param trim Null-terminated set of characters to trim from the start and end of each token.
+ * \param trim_empty Whether to trim empty tokens and consecutive delimiters.
  * \return Number of tokens stored in @split_map.
  *
  * Example:
- *   char  buf[] = "  one,two,,three  ";
+ *   char  buf[] = "  one, two,, , three  ";
  *   char* map[8];
- *   unsigned n = strsplit(map, 8, buf, " ,");
+ *   unsigned n = strsplit(map, 8, buf, ",", " ", 1);
  *   // n == 3, map[] == { "one", "two", "three" }
  */
-unsigned strsplit(char** split_map, unsigned split_max, char* str, const char* delimiters);
+unsigned strsplit(char** split_map, unsigned split_max, char* str, const char* delimiters, const char* trim, int trim_empty);
 
 /**
  * Split a command-line string into an argument vector,

cmdline/unixapp.c

@@ -873,8 +873,8 @@ static int devdereference_bcachefs(uint64_t device, const char* dir, tommy_list*
 		separator += 3;
 
 		/* split the line */
-		id_mac = strsplit(id_map, 8, s, " \t\n");
-		fs_mac = strsplit(fs_map, 8, separator, " \t\n");
+		id_mac = strsplit(id_map, 8, s, " \t\r\n", 0, 1);
+		fs_mac = strsplit(fs_map, 8, separator, " \t\r\n", 0, 1);
 
 		/* if too short, it's the wrong line */
 		if (id_mac < 5)
@@ -914,7 +914,7 @@ static int devdereference_bcachefs(uint64_t device, const char* dir, tommy_list*
 
 	/* split the device list */
 	char* dev_map[64];
-	unsigned dev_mac = strsplit(dev_map, 64, device_list, ":");
+	unsigned dev_mac = strsplit(dev_map, 64, device_list, ":", 0, 0);
 	for (unsigned i = 0; i < dev_mac; ++i) {
 		/* get major:minor, use stat on the path returned */
 		struct stat st;
@@ -998,7 +998,7 @@ static int extract_zfs(const char* dir, char* dataset, size_t dataset_size, char
 			break;
 
 		/* split the line */
-		mac = strsplit(map, 3, s, "\t\n");
+		mac = strsplit(map, 3, s, "\t\r\n", 0, 1);
 
 		if (mac < 3)
 			continue;