utils: Add helper routines for indent handling

Subsequent patch needs to use 2 char indentation for nested objects.
Hence introduce a generic helpers to allocate, deallocate, increment,
decrement and to print indent block.

Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: David Ahern <dsahern@kernel.org>

include/utils.h

@@ -349,4 +349,20 @@ int str_map_lookup_str(const struct str_num_map *map, const char *needle);
 const char *str_map_lookup_u16(const struct str_num_map *map, uint16_t val);
 const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val);
 
+unsigned int get_str_char_count(const char *str, int match);
+int str_split_by_char(char *str, char **before, char **after, int match);
+
+#define INDENT_STR_MAXLEN 32
+
+struct indent_mem {
+	int indent_level;
+	char indent_str[INDENT_STR_MAXLEN + 1];
+};
+
+struct indent_mem *alloc_indent_mem(void);
+void free_indent_mem(struct indent_mem *mem);
+void inc_indent(struct indent_mem *mem);
+void dec_indent(struct indent_mem *mem);
+void print_indent(struct indent_mem *mem);
+
 #endif /* __UTILS_H__ */

lib/utils.c

@@ -1978,3 +1978,69 @@ const char *str_map_lookup_u8(const struct str_num_map *map, uint8_t val)
 	}
 	return NULL;
 }
+
+unsigned int get_str_char_count(const char *str, int match)
+{
+	unsigned int count = 0;
+	const char *pos = str;
+
+	while ((pos = strchr(pos, match))) {
+		count++;
+		pos++;
+	}
+	return count;
+}
+
+int str_split_by_char(char *str, char **before, char **after, int match)
+{
+	char *slash;
+
+	slash = strrchr(str, match);
+	if (!slash)
+		return -EINVAL;
+	*slash = '\0';
+	*before = str;
+	*after = slash + 1;
+	return 0;
+}
+
+struct indent_mem *alloc_indent_mem(void)
+{
+	struct indent_mem *mem = malloc(sizeof(*mem));
+
+	if (!mem)
+		return NULL;
+	strcpy(mem->indent_str, "");
+	mem->indent_level = 0;
+	return mem;
+}
+
+void free_indent_mem(struct indent_mem *mem)
+{
+	free(mem);
+}
+
+#define INDENT_STR_STEP 2
+
+void inc_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level + INDENT_STR_STEP > INDENT_STR_MAXLEN)
+		return;
+	mem->indent_level += INDENT_STR_STEP;
+	memset(mem->indent_str, ' ', sizeof(mem->indent_str));
+	mem->indent_str[mem->indent_level] = '\0';
+}
+
+void dec_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level - INDENT_STR_STEP < 0)
+		return;
+	mem->indent_level -= INDENT_STR_STEP;
+	mem->indent_str[mem->indent_level] = '\0';
+}
+
+void print_indent(struct indent_mem *mem)
+{
+	if (mem->indent_level)
+		printf("%s", mem->indent_str);
+}