1 files changed, 151 insertions, 0 deletions
diff --git a/pg_array.c b/pg_array.c
new file mode 100644
index 0000000..7b1cd23
--- /dev/null
+++ b/pg_array.c
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+/*-------------------------------------------------------------------------
+ * pg_array.c
+ *
+ *      Functions for libpq array manipulation
+ *      This is intended to contain functions to manage libpq arrays.
+ *      This isn't likely to be comprehensive
+ *
+ *      Copyright (c) 2004-2007, PostgreSQL Global Development Group
+ *      Author: Joshua Tolley
+ *
+ * $Id: pg_array.c,v 1.6 2007/09/13 14:20:43 h-saito Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "pg_array.h"
+
+/* Text array format consists of leading and trailing curly braces. Values containing
+ * characters that might be confusing (backslashes, double-quotes, etc.) are double-
+ * quoted, and confusing characters are backslash-escaped */
+
+/* pg_text_array_parse()
+* Takes an input string as returned by PQgetvalue(), parses it as a text array, and
+ * builds an array of strings, which it returns, or NULL on error. pg_text_array also
+ * sets len to the number of strings in the array. THE USER IS RESPONSIBLE
+ * FOR FREEING CHAR ***OUTPUT, perhaps by calling pg_text_array_free. */
+
+/* TODO: Add debugging/logging */
+
+char ** pg_text_array_parse(char *input, int *len) {
+	char **results = NULL, **tmp;
+	char *incursor, *outcursor, *output, *start_element;
+	int escaped = 0, done_single_element = 0, done_all_elements = 0, i,
+		 cursorlen, inputlen, elements = 0, outputlen, error = 0, in_quotes = 0;
+
+	inputlen = strlen(input);
+	if (!inputlen || inputlen < 3 || SIZE_MAX / inputlen < sizeof(char*)) return NULL;
+	incursor = input + 1;
+	while (!done_all_elements) {
+		in_quotes = 0;
+		if (*incursor == '"') {
+			incursor++;
+			in_quotes = 1;
+		}
+/*		else if (*incursor == ',') break; */
+		start_element = incursor;
+		outcursor = strpbrk(incursor, ",}");
+		if (!outcursor) return NULL;
+		/* FACT: outcursor - incursor >= 1 */
+		outputlen = outcursor - incursor + 1;
+		output = calloc(outputlen, sizeof(char));
+		if (!output) return NULL;
+		outcursor = output;
+		done_single_element = 0;
+		while (!done_single_element) {
+			if (!escaped) {
+				switch (*incursor) {
+					case '}': 
+						done_single_element = 1;
+						done_all_elements = 1;
+						break;
+					case ',':
+						if (!in_quotes) done_single_element = 1;
+						break;
+					case '"':
+						in_quotes = 0;
+						done_single_element = 1;
+						incursor++;
+						if (*incursor == '}') done_all_elements = 1;
+						break;
+				}
+			}
+			if (!done_single_element) {
+				if (!escaped && *incursor == '\\') escaped = 1;
+				else {
+					if (outcursor - output >= outputlen) {
+						cursorlen = outcursor - output;
+						outcursor = strpbrk(incursor + 1, ",}");
+						if (!outcursor) {
+							error = 1;
+							break;
+						}
+						outputlen = outcursor - start_element;
+						outcursor = realloc(output, outputlen * sizeof(char));
+						if (!outcursor) {
+							error = 1;
+							break;
+						}
+						output = outcursor;
+						outcursor = output + cursorlen;
+					}
+					if (escaped) {
+						escaped = 0;
+						*outcursor = *incursor;
+						outcursor++;
+					}
+					else {
+						*outcursor = *incursor;
+						outcursor++;
+					}
+				}
+			}
+			if (done_single_element) {
+				elements++;
+				memset(outcursor, 0, outputlen - (outcursor - output));
+				if (results) {
+					tmp = realloc(results, elements * sizeof(char*));
+					if (!tmp) {
+						error = 1;
+						break;
+					}
+					results = tmp;
+				}
+				else {
+					results = calloc(1, sizeof(char*));
+					if (!results) {
+						error = 1;
+						break;
+					}
+				}
+				results[elements - 1] = output;
+			}
+			if (!done_all_elements) {
+				incursor++;
+				if (incursor - input >= inputlen) {
+					error = 1;
+					break;
+				}
+			}
+		}
+		if (error) break;
+	}
+	if (error) {
+		for (i = 0; i < elements; i++)
+			free(results[i]);
+		free(results);
+		free(output);
+		return NULL;
+	}
+	*len = elements;
+	return results;
+}
+
+/* pg_text_array_free() 
+ * Frees an array of strings such as is returned by pg_text_array_parse() */
+void pg_text_array_free(char **array, int len) {
+	int i;
+	for (i = 0; i < len; i++)
+		free(array[i]);
+	free(array);
+}