From a1ce94eed364952e8998def4e964ecb6b33b977d Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@openwrt.org>
Date: Sun, 20 Jan 2008 19:39:47 +0100
Subject: [PATCH] print the reason for parse errors in error messages

---
 libuci.c |  2 +-
 parse.c  | 15 ++++++++++-----
 uci.h    |  1 +
 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/libuci.c b/libuci.c
index 262ca69..cb0bc36 100644
--- a/libuci.c
+++ b/libuci.c
@@ -116,7 +116,7 @@ void uci_perror(struct uci_context *ctx, const char *str)
 	switch (err) {
 	case UCI_ERR_PARSE:
 		if (ctx->pctx) {
-			fprintf(stderr, "%s: %s at line %d, byte %d\n", str, uci_errstr[err], ctx->pctx->line, ctx->pctx->byte);
+			fprintf(stderr, "%s: %s (%s) at line %d, byte %d\n", str, uci_errstr[err], (ctx->pctx->reason ? ctx->pctx->reason : "unknown"), ctx->pctx->line, ctx->pctx->byte);
 			break;
 		}
 		/* fall through */
diff --git a/parse.c b/parse.c
index 4c51715..31756d9 100644
--- a/parse.c
+++ b/parse.c
@@ -56,6 +56,7 @@ static void uci_getln(struct uci_context *ctx)
 		}
 
 		if (pctx->bufsz > LINEBUF_MAX/2) {
+			pctx->reason = "line too long";
 			pctx->byte = LINEBUF_MAX;
 			UCI_THROW(ctx, UCI_ERR_PARSE);
 		}
@@ -137,6 +138,7 @@ static void parse_double_quote(struct uci_context *ctx, char **str, char **targe
 			break;
 		}
 	}
+	ctx->pctx->reason = "unterminated \"";
 	ctx->pctx->byte = *str - ctx->pctx->buf;
 	UCI_THROW(ctx, UCI_ERR_PARSE);
 }
@@ -160,6 +162,7 @@ static void parse_single_quote(struct uci_context *ctx, char **str, char **targe
 			addc(target, str);
 		}
 	}
+	ctx->pctx->reason = "unterminated '";
 	ctx->pctx->byte = *str - ctx->pctx->buf;
 	UCI_THROW(ctx, UCI_ERR_PARSE);
 }
@@ -213,6 +216,7 @@ static char *next_arg(struct uci_context *ctx, char **str, bool required)
 	skip_whitespace(str);
 	parse_str(ctx, str, &ptr);
 	if (required && !*val) {
+		ctx->pctx->reason = "insufficient arguments";
 		ctx->pctx->byte = *str - ctx->pctx->buf;
 		UCI_THROW(ctx, UCI_ERR_PARSE);
 	}
@@ -230,6 +234,7 @@ static void assert_eol(struct uci_context *ctx, char **str)
 
 	tmp = next_arg(ctx, str, false);
 	if (tmp && *tmp) {
+		ctx->pctx->reason = "too many arguments";
 		ctx->pctx->byte = tmp - ctx->pctx->buf;
 		UCI_THROW(ctx, UCI_ERR_PARSE);
 	}
@@ -242,16 +247,14 @@ static void uci_parse_config(struct uci_context *ctx, char **str)
 {
 	char *type, *name;
 
+	/* command string null-terminated by strtok */
 	*str += strlen(*str) + 1;
 
-	if (!*str) {
-		ctx->pctx->byte = *str - ctx->pctx->buf;
-		UCI_THROW(ctx, UCI_ERR_PARSE);
-	}
-
 	type = next_arg(ctx, str, true);
 	name = next_arg(ctx, str, false);
 	assert_eol(ctx, str);
+
+	DPRINTF("Section<%s>: %s\n", type, name);
 }
 
 /*
@@ -261,6 +264,7 @@ static void uci_parse_option(struct uci_context *ctx, char **str)
 {
 	char *name, *value;
 
+	/* command string null-terminated by strtok */
 	*str += strlen(*str) + 1;
 
 	name = next_arg(ctx, str, true);
@@ -295,6 +299,7 @@ static void uci_parse_line(struct uci_context *ctx)
 					uci_parse_option(ctx, &word);
 				break;
 			default:
+				pctx->reason = "unterminated command";
 				pctx->byte = word - pctx->buf;
 				UCI_THROW(ctx, UCI_ERR_PARSE);
 				break;
diff --git a/uci.h b/uci.h
index 4706255..c558696 100644
--- a/uci.h
+++ b/uci.h
@@ -97,6 +97,7 @@ struct uci_parse_context
 	struct uci_config *cfg;
 	FILE *file;
 	char *buf;
+	char *reason;
 	int bufsz;
 };
 
-- 
2.41.1