WT-2998 add error messages to error returns that might be confusing. (#3110)

4 files changed, 81 insertions, 26 deletions

diff --git a/ext/compressors/zlib/zlib_compress.c b/ext/compressors/zlib/zlib_compress.c
index 9ee8fe3bd8b..0539569015f 100644
--- a/ext/compressors/zlib/zlib_compress.c
+++ b/ext/compressors/zlib/zlib_compress.c
@@ -392,19 +392,27 @@ err:	if ((tret = deflateEnd(zs)) != Z_OK && tret != Z_DATA_ERROR)
 #if 0
 	/* Decompress the result and confirm it matches the original source. */
 	if (ret == 0 && last_slot > 0) {
+		WT_EXTENSION_API *wt_api;
 		void *decomp;
 		size_t result_len;
 
+		wt_api = ((ZLIB_COMPRESSOR *)compressor)->wt_api;
+
 		if ((decomp = zalloc(
-		    &opaque, 1, (uint32_t)best_zs->total_in + 100)) == NULL)
+		    &opaque, 1, (uint32_t)best_zs->total_in + 100)) == NULL) {
+			(void)wt_api->err_printf(wt_api, session,
+			    "zlib_compress_raw: zalloc failure");
 			return (ENOMEM);
+		}
 		if ((ret = zlib_decompress(
 		    compressor, session, dst, (size_t)best_zs->total_out,
 		    decomp, (size_t)best_zs->total_in + 100, &result_len)) == 0)
-			 if (memcmp(src, decomp, result_len) != 0)
-				ret = zlib_error(compressor, session,
-				    "deflate compare with original source",
-				    Z_DATA_ERROR);
+			if (memcmp(src, decomp, result_len) != 0) {
+				(void)wt_api->err_printf(wt_api, session,
+				    "zlib_compress_raw: "
+				    "deflate compare with original source");
+				return (WT_ERROR);
+			}
 		zfree(&opaque, decomp);
 	}
 #endif
diff --git a/ext/encryptors/nop/nop_encrypt.c b/ext/encryptors/nop/nop_encrypt.c
index eac7d8f4632..eb311f09909 100644
--- a/ext/encryptors/nop/nop_encrypt.c
+++ b/ext/encryptors/nop/nop_encrypt.c
@@ -38,13 +38,29 @@
 typedef struct {
 	WT_ENCRYPTOR encryptor;		/* Must come first */
 
-	WT_EXTENSION_API *wt_api;		/* Extension API */
+	WT_EXTENSION_API *wtext;	/* Extension API */
 
-	unsigned long nop_calls;		/* Count of calls */
+	unsigned long nop_calls;	/* Count of calls */
 
 } NOP_ENCRYPTOR;
 /*! [WT_ENCRYPTOR initialization structure] */
 
+/*
+ * nop_error --
+ *	Display an error from this module in a standard way.
+ */
+static int
+nop_error(
+    NOP_ENCRYPTOR *encryptor, WT_SESSION *session, int err, const char *msg)
+{
+	WT_EXTENSION_API *wtext;
+
+	wtext = encryptor->wtext;
+	(void)wtext->err_printf(wtext, session,
+	    "nop encryption: %s: %s", msg, wtext->strerror(wtext, NULL, err));
+	return (err);
+}
+
 /*! [WT_ENCRYPTOR encrypt] */
 /*
  * nop_encrypt --
@@ -63,7 +79,8 @@ nop_encrypt(WT_ENCRYPTOR *encryptor, WT_SESSION *session,
 	++nop_encryptor->nop_calls;		/* Call count */
 
 	if (dst_len < src_len)
-		return (ENOMEM);
+		return (nop_error(nop_encryptor, session,
+		    ENOMEM, "encrypt buffer not big enough"));
 
 	memcpy(dst, src, src_len);
 	*result_lenp = src_len;
@@ -169,7 +186,7 @@ wiredtiger_extension_init(WT_CONNECTION *connection, WT_CONFIG_ARG *config)
 	nop_encryptor->encryptor.sizing = nop_sizing;
 	nop_encryptor->encryptor.terminate = nop_terminate;
 
-	nop_encryptor->wt_api = connection->get_extension_api(connection);
+	nop_encryptor->wtext = connection->get_extension_api(connection);
 
 						/* Load the encryptor */
 	return (connection->add_encryptor(
diff --git a/ext/encryptors/rotn/rotn_encrypt.c b/ext/encryptors/rotn/rotn_encrypt.c
index 4d614e2e409..23a7ad79a7d 100644
--- a/ext/encryptors/rotn/rotn_encrypt.c
+++ b/ext/encryptors/rotn/rotn_encrypt.c
@@ -89,8 +89,8 @@ typedef struct {
  *	Display an error from this module in a standard way.
  */
 static int
-rotn_error(ROTN_ENCRYPTOR *encryptor, WT_SESSION *session, int err,
-    const char *msg)
+rotn_error(
+    ROTN_ENCRYPTOR *encryptor, WT_SESSION *session, int err, const char *msg)
 {
 	WT_EXTENSION_API *wtext;
 
@@ -189,7 +189,8 @@ rotn_encrypt(WT_ENCRYPTOR *encryptor, WT_SESSION *session,
 	(void)session;		/* Unused */
 
 	if (dst_len < src_len + CHKSUM_LEN + IV_LEN)
-		return (ENOMEM);
+		return (rotn_error(rotn_encryptor, session,
+		    ENOMEM, "encrypt buffer not big enough"));
 
 	/*
 	 * !!! Most implementations would verify any needed
@@ -333,7 +334,8 @@ rotn_customize(WT_ENCRYPTOR *encryptor, WT_SESSION *session,
 		 * In this demonstration, we expect keyid to be a number.
 		 */
 		if ((keyid_val = atoi(keyid.str)) < 0) {
-			ret = EINVAL;
+			ret = rotn_error(rotn_encryptor,
+			    NULL, EINVAL, "rotn_customize: invalid keyid");
 			goto err;
 		}
 		if ((rotn_encryptor->keyid = malloc(keyid.len + 1)) == NULL) {
@@ -364,7 +366,8 @@ rotn_customize(WT_ENCRYPTOR *encryptor, WT_SESSION *session,
 			else if ('A' <= secret.str[i] && secret.str[i] <= 'Z')
 				base = 'A';
 			else {
-				ret = EINVAL;
+				ret = rotn_error(rotn_encryptor, NULL,
+				    EINVAL, "rotn_customize: invalid key");
 				goto err;
 			}
 			base -= (u_char)keyid_val;
diff --git a/ext/extractors/csv/csv_extractor.c b/ext/extractors/csv/csv_extractor.c
index 698a9d6fa96..40e03f7ec1a 100644
--- a/ext/extractors/csv/csv_extractor.c
+++ b/ext/extractors/csv/csv_extractor.c
@@ -54,6 +54,22 @@ typedef struct {
 } CSV_EXTRACTOR;
 
 /*
+ * csv_error --
+ *	Display an error from this module in a standard way.
+ */
+static int
+csv_error(const CSV_EXTRACTOR *csv_extractor,
+    WT_SESSION *session, int err, const char *msg)
+{
+	WT_EXTENSION_API *wt_api;
+
+	wt_api = csv_extractor->wt_api;
+	(void)wt_api->err_printf(wt_api, session,
+	    "csv extraction: %s: %s", msg, wt_api->strerror(wt_api, NULL, err));
+	return (err);
+}
+
+/*
  * csv_extract --
  *	WiredTiger CSV extraction.
  */
@@ -61,11 +77,11 @@ static int
 csv_extract(WT_EXTRACTOR *extractor, WT_SESSION *session,
     const WT_ITEM *key, const WT_ITEM *value, WT_CURSOR *result_cursor)
 {
-	char *copy, *p, *pend, *valstr;
 	const CSV_EXTRACTOR *csv_extractor;
-	int i, ret, val;
-	size_t len;
 	WT_EXTENSION_API *wtapi;
+	size_t len;
+	int i, ret, val;
+	char *copy, *p, *pend, *valstr;
 
 	(void)key;				/* Unused parameters */
 
@@ -98,8 +114,10 @@ csv_extract(WT_EXTRACTOR *extractor, WT_SESSION *session,
 		copy[len] = '\0';
 		if (csv_extractor->format_isnum) {
 			if ((val = atoi(copy)) < 0) {
+				ret = csv_error(csv_extractor,
+				    session, EINVAL, "invalid key value");
 				free(copy);
-				return (EINVAL);
+				return (ret);
 			}
 			result_cursor->set_key(result_cursor, val);
 		} else
@@ -125,29 +143,38 @@ csv_customize(WT_EXTRACTOR *extractor, WT_SESSION *session,
 	CSV_EXTRACTOR *csv_extractor;
 	WT_CONFIG_ITEM field, format;
 	WT_CONFIG_PARSER *parser;
-	WT_EXTENSION_API *wtapi;
-	int ret;
+	WT_EXTENSION_API *wt_api;
 	long field_num;
+	int ret;
 
 	(void)session;				/* Unused parameters */
 	(void)uri;				/* Unused parameters */
 
 	orig = (const CSV_EXTRACTOR *)extractor;
-	wtapi = orig->wt_api;
-	if ((ret = wtapi->config_parser_open(wtapi, session, appcfg->str,
+	wt_api = orig->wt_api;
+	if ((ret = wt_api->config_parser_open(wt_api, session, appcfg->str,
 	    appcfg->len, &parser)) != 0)
 		return (ret);
 	if ((ret = parser->get(parser, "field", &field)) != 0 ||
 	    (ret = parser->get(parser, "format", &format)) != 0) {
-		if (ret == WT_NOTFOUND)
-			return (EINVAL);
+		if (ret == WT_NOTFOUND) {
+			(void)wt_api->err_printf(
+			    wt_api, session, "field or format not found");
+			return (WT_NOTFOUND);
+		}
 		return (ret);
 	}
 	field_num = strtol(field.str, NULL, 10);
-	if (field_num < 0 || field_num > INT_MAX)
+	if (field_num < 0 || field_num > INT_MAX) {
+		(void)wt_api->err_printf(
+		    wt_api, session, "field: invalid format");
 		return (EINVAL);
-	if (format.len != 1 || (format.str[0] != 'S' && format.str[0] != 'i'))
+	}
+	if (format.len != 1 || (format.str[0] != 'S' && format.str[0] != 'i')) {
+		(void)wt_api->err_printf(
+		    wt_api, session, "format: invalid format");
 		return (EINVAL);
+	}
 	if ((csv_extractor = calloc(1, sizeof(CSV_EXTRACTOR))) == NULL)
 		return (errno);