Add a helper to libutil for splitting token separated lines

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 109 insertions, 0 deletions

diff --git a/lib/util/src/split_line.c b/lib/util/src/split_line.c
new file mode 100644
index 0000000..ede9964
--- /dev/null
+++ b/lib/util/src/split_line.c
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * split_line.c
+ *
+ * Copyright (C) 2023 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "util/parse.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+static split_line_t *append_arg(split_line_t *in, char *arg)
+{
+	split_line_t *out = realloc(in, sizeof(*in) +
+				    (in->count + 1) * sizeof(char *));
+
+	if (out == NULL) {
+		free(in);
+		return NULL;
+	}
+
+	out->args[out->count++] = arg;
+	return out;
+}
+
+static int is_sep(const char *sep, int c)
+{
+	return strchr(sep, c) != NULL && c != '\0';
+}
+
+int split_line(char *line, size_t len, const char *sep, split_line_t **out)
+{
+	split_line_t *split = calloc(1, sizeof(*split));
+	char *src = line, *dst = line;
+
+	if (split == NULL)
+		return SPLIT_LINE_ALLOC;
+
+	while (len > 0 && is_sep(sep, *src)) {
+		++src;
+		--len;
+	}
+
+	while (len > 0 && *src != '\0') {
+		split = append_arg(split, dst);
+		if (split == NULL)
+			return SPLIT_LINE_ALLOC;
+
+		if (*src == '"') {
+			++src;
+			--len;
+
+			while (len > 0 && *src != '\0' && *src != '"') {
+				if (src[0] == '\\') {
+					if (len < 2)
+						goto fail_esc;
+					if (src[1] != '"' && src[1] != '\\')
+						goto fail_esc;
+
+					*(dst++) = src[1];
+					src += 2;
+					len -= 2;
+				} else {
+					*(dst++) = *(src++);
+					--len;
+				}
+			}
+
+			if (len == 0 || *src != '"')
+				goto fail_quote;
+			++src;
+			--len;
+		} else {
+			while (len > 0 && !is_sep(sep, *src) && *src != '\0') {
+				*(dst++) = *(src++);
+				--len;
+			}
+		}
+
+		while (len > 0 && is_sep(sep, *src)) {
+			++src;
+			--len;
+		}
+
+		*(dst++) = '\0';
+	}
+
+	*out = split;
+	return SPLIT_LINE_OK;
+fail_esc:
+	free(split);
+	return SPLIT_LINE_ESCAPE;
+fail_quote:
+	free(split);
+	return SPLIT_LINE_UNMATCHED_QUOTE;
+}
+
+void split_line_remove_front(split_line_t *split, size_t count)
+{
+	if (count < split->count) {
+		for (size_t i = count, j = 0; i < split->count; ++i, ++j)
+			split->args[j] = split->args[i];
+		split->count -= count;
+	} else {
+		split->count = 0;
+	}
+}