Print the system error message, if the input or output file could not be opened.

frontend/src/crypt.c

@@ -20,6 +20,7 @@
 #include <inttypes.h>
 #include <ctype.h>
 #include <assert.h>
+#include <errno.h>
 
 // ==========================================================================
 // Constants
@@ -37,14 +38,14 @@ static int open_files(FILE **const file_in, FILE **const file_out, const CHR *co
 {
 	if (!(*file_in = FOPEN(input_path, T("rb"))))
 	{
-		FPRINTF(stderr, T("Error: Failed to open input file \"%") T(PRISTR) T("\" for reading!\n\n"), input_path);
+		FPRINTF(stderr, T("Error: Failed to open input file \"%") T(PRISTR) T("\" for reading!\n\n%") T(PRISTR) T("\n\n"), input_path, STRERROR(errno));
 		*file_out = NULL;
 		return EXIT_FAILURE;
 	}
 
 	if (!(*file_out = FOPEN(output_path, T("wb"))))
 	{
-		FPRINTF(stderr, T("Error: Failed to open output file \"%") T(PRISTR) T("\" for writing!\n\n"), output_path);
+		FPRINTF(stderr, T("Error: Failed to open output file \"%") T(PRISTR) T("\" for writing!\n\n%") T(PRISTR) T("\n\n"), output_path, STRERROR(errno));
 		return EXIT_FAILURE;
 	}
 

frontend/src/platform.h

@@ -63,6 +63,7 @@
 #	define FPRINTF(X,Y,...) fwprintf((X),(Y),__VA_ARGS__)
 #	define REMOVE(X) _wremove((X))
 #	define FOPEN(X,Y) _wfsopen((X),(Y),_SH_SECURE)
+#	define STRERROR(X) _wcserror((X))
 #	ifdef __USE_MINGW_ANSI_STDIO
 #		define PRISTR "ls"
 #		define PRIstr "hs"
@@ -87,6 +88,7 @@
 #	define FPRINTF(X,Y,...) fprintf((X),(Y),__VA_ARGS__)
 #	define REMOVE(X) remove((X))
 #	define FOPEN(X,Y) fopen((X),(Y))
+#	define STRERROR(X) strerror((X))
 #	define PRISTR "s"
 #	define PRIstr "s"
 #	define PRIwcs "ls"

frontend/src/pwgen.c

@@ -16,6 +16,7 @@
 
 /* CRT */
 #include <ctype.h>
+#include <errno.h>
 
 // ==========================================================================
 // Constants
@@ -37,51 +38,70 @@ static const char PASSWD_SYMBOLS[] =
 // Read passphrase from file
 // ==========================================================================
 
+#define PASSPHRASE_BUFFSIZE (SLUNKCRYPT_PWDLEN_MAX + 2U)
+
 char *read_passphrase(const CHR *const file_name)
 {
+	size_t str_len = 0U;
+	CHR  *passphrase_path = NULL;
+	char *buffer = NULL;
+	FILE *passphrase_file = NULL;
+
 	if ((!file_name) || (!file_name[0U]))
 	{
 		FPUTS(T("Error: The passphrase input file name must not be empty!\n\n"), stderr);
-		return NULL;
+		goto finish;
 	}
 
-	const size_t max_len = SLUNKCRYPT_PWDLEN_MAX + 2U;
+	if (STRICMP(file_name, T("-")))
-	char *const buffer = (char*) malloc(max_len * sizeof(char));
+	{
+		passphrase_path = absolute_path(file_name);
+		if ((!passphrase_path) || (!passphrase_path[0U]))
+		{
+			FPUTS(T("Error: Passphrase input file path could not be resolved!\n\n"), stderr);
+			goto finish;
+		}
+	}
+
+	passphrase_file = passphrase_path ? FOPEN(passphrase_path, T("rb")): stdin;
+	if (!passphrase_file)
+	{
+		FPRINTF(stderr, T("Error: Failed to open passphrase file \"%") T(PRISTR) T("\" for reading!\n\n%") T(PRISTR) T("\n\n"), passphrase_path, STRERROR(errno));
+		goto finish;
+	}
+
+	buffer = (char*) calloc(PASSPHRASE_BUFFSIZE, sizeof(char));
 	if (!buffer)
 	{
 		FPUTS(T("Error: Failed to allocate the passphrase buffer!\n\n"), stderr);
-		return NULL;
+		goto finish;
-	}
-
-	const int use_stdin = (!file_name) || (!STRICMP(file_name, T("-")));
-	FILE *const file_in = use_stdin ? stdin : FOPEN(file_name, T("rb"));
-	if (!file_in)
-	{
-		FPRINTF(stderr, T("Error: Failed to open input file \"%") T(PRISTR) T("\" for reading!\n\n"), file_name);
-		free(buffer);
-		return NULL;
 	}
 
 	do
 	{
-		if (!fgets(buffer, (int)max_len, file_in))
+		if (!fgets(buffer, (int)PASSPHRASE_BUFFSIZE, passphrase_file))
 		{
 			buffer[0U] = '\0';
 			goto finish;
 		}
-		size_t length = strlen(buffer);
+		str_len = strlen(buffer);
-		while ((length > 0U) && ((buffer[length - 1U] == '\r') || (buffer[length - 1U] == '\n')))
+		while ((str_len > 0U) && ((buffer[str_len - 1U] == '\r') || (buffer[str_len - 1U] == '\n')))
 		{
-			buffer[--length] = '\0';
+			buffer[--str_len] = '\0';
 		}
 	}
 	while (!buffer[0U]);
 
 finish:
 
-	if ((!use_stdin) && file_in)
+	if (passphrase_file && (passphrase_file != stdin))
 	{
-		fclose(file_in);
+		fclose(passphrase_file);
+	}
+
+	if (passphrase_path)
+	{
+		free(passphrase_path);
 	}
 
 	return buffer;