libmpdclient: smaller error buffer

512 characters should be well enough for error messages which are
actually being displayed somewhere.  Use sizeof(errorStr) instead of
MPD_BUFFER_MAX_LENGTH everywhere.  Do proper length checking when
copying the output buffer to errorStr.

diff --git a/src/libmpdclient.c b/src/libmpdclient.c
index 8d1670f96951d79adc3fbde3a82e91450f90a345..b29ffe746527fda3c0cf9520d21b25dd4834746f 100644 (file)
--- a/src/libmpdclient.c
+++ b/src/libmpdclient.c
@@ -87,7 +87,7 @@ static int winsock_dll_error(mpd_Connection *connection)
        if ((WSAStartup(MAKEWORD(2, 2), &wsaData)) != 0 ||
                        LOBYTE(wsaData.wVersion) != 2 ||
                        HIBYTE(wsaData.wVersion) != 2 ) {
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "Could not find usable WinSock DLL.");
                connection->error = MPD_ERROR_SYSTEM;
                return 1;
@@ -141,7 +141,7 @@ static int mpd_connect(mpd_Connection * connection, const char * host, int port,
        error = getaddrinfo(host, service, &hints, &addrinfo);
 
        if (error) {
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "host \"%s\" not found: %s",host, gai_strerror(error));
                connection->error = MPD_ERROR_UNKHOST;
                return -1;
@@ -151,7 +151,7 @@ static int mpd_connect(mpd_Connection * connection, const char * host, int port,
                /* create socket */
                connection->sock = socket(res->ai_family, SOCK_STREAM, res->ai_protocol);
                if (connection->sock < 0) {
-                       snprintf(connection->errorStr, MPD_BUFFER_MAX_LENGTH,
+                       snprintf(connection->errorStr, sizeof(connection->errorStr),
                                 "problems creating socket: %s",
                                 strerror(errno));
                        connection->error = MPD_ERROR_SYSTEM;
@@ -172,7 +172,7 @@ static int mpd_connect(mpd_Connection * connection, const char * host, int port,
        freeaddrinfo(addrinfo);
 
        if (connection->sock < 0) {
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "problems connecting to \"%s\" on port"
                         " %i: %s",host,port, strerror(errno));
                connection->error = MPD_ERROR_CONNPORT;
@@ -192,7 +192,7 @@ static int mpd_connect(mpd_Connection * connection, const char * host, int port,
        struct sockaddr_in sin;
 
        if(!(he=gethostbyname(host))) {
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "host \"%s\" not found",host);
                connection->error = MPD_ERROR_UNKHOST;
                return -1;
@@ -227,7 +227,7 @@ static int mpd_connect(mpd_Connection * connection, const char * host, int port,
 
        /* connect stuff */
        if (do_connect_fail(connection, dest, destlen)) {
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "problems connecting to \"%s\" on port"
                         " %i",host,port);
                connection->error = MPD_ERROR_CONNPORT;
@@ -306,7 +306,7 @@ static int mpd_parseWelcome(mpd_Connection * connection, const char * host, int
        int i;
 
        if(strncmp(output,MPD_WELCOME_MESSAGE,strlen(MPD_WELCOME_MESSAGE))) {
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "mpd not running on port %i on host \"%s\"",
                         port,host);
                connection->error = MPD_ERROR_NOTMPD;
@@ -319,8 +319,7 @@ static int mpd_parseWelcome(mpd_Connection * connection, const char * host, int
                if(tmp) connection->version[i] = strtol(tmp,&test,10);
 
                if (!tmp || (test[0] != '.' && test[0] != '\0')) {
-                       snprintf(connection->errorStr,
-                                MPD_BUFFER_MAX_LENGTH,
+                       snprintf(connection->errorStr, sizeof(connection->errorStr),
                                 "error parsing version number at "
                                 "\"%s\"",
                                 &output[strlen(MPD_WELCOME_MESSAGE)]);
@@ -369,7 +368,7 @@ static int mpd_connect_un(mpd_Connection * connection,
                close(connection->sock);
                connection->sock = 0;
 
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "problems connecting to \"%s\": %s",
                         host, strerror(errno));
                connection->error = MPD_ERROR_CONNPORT;
@@ -389,8 +388,7 @@ mpd_Connection * mpd_newConnection(const char * host, int port, float timeout) {
 
        connection->buflen = 0;
        connection->bufstart = 0;
-       strcpy(connection->errorStr,"");
-       connection->error = 0;
+       mpd_clearError(connection);
        connection->doneProcessing = 0;
        connection->commandList = 0;
        connection->listOks = 0;
@@ -421,7 +419,7 @@ mpd_Connection * mpd_newConnection(const char * host, int port, float timeout) {
                                      &(connection->buffer[connection->buflen]),
                                      MPD_BUFFER_MAX_LENGTH-connection->buflen,0);
                        if(readed<=0) {
-                               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+                               snprintf(connection->errorStr, sizeof(connection->errorStr),
                                         "problems getting a response from"
                                         " \"%s\" on port %i : %s",host,
                                         port, strerror(errno));
@@ -434,14 +432,14 @@ mpd_Connection * mpd_newConnection(const char * host, int port, float timeout) {
                        if (SELECT_ERRNO_IGNORE)
                                continue;
                        snprintf(connection->errorStr,
-                                MPD_BUFFER_MAX_LENGTH,
+                                sizeof(connection->errorStr),
                                 "problems connecting to \"%s\" on port"
                                 " %i",host,port);
                        connection->error = MPD_ERROR_CONNPORT;
                        return connection;
                }
                else {
-                       snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+                       snprintf(connection->errorStr, sizeof(connection->errorStr),
                                 "timeout in attempting to get a response from"
                                 " \"%s\" on port %i",host,port);
                        connection->error = MPD_ERROR_NORESPONSE;
@@ -500,7 +498,7 @@ static void mpd_executeCommand(mpd_Connection *connection,
                if(ret<=0)
                {
                        if (SENDRECV_ERRNO_IGNORE) continue;
-                       snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+                       snprintf(connection->errorStr, sizeof(connection->errorStr),
                                 "problems giving command \"%s\"",command);
                        connection->error = MPD_ERROR_SENDING;
                        return;
@@ -515,7 +513,7 @@ static void mpd_executeCommand(mpd_Connection *connection,
 
        if(commandLen>0) {
                perror("");
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "timeout sending command \"%s\"",command);
                connection->error = MPD_ERROR_TIMEOUT;
                return;
@@ -631,11 +629,16 @@ static void mpd_getNextReturnElement(mpd_Connection * connection) {
        }
 
        if(strncmp(output,"ACK",strlen("ACK"))==0) {
+               size_t length = strlen(output);
                char * test;
                char * needle;
                int val;
 
-               strcpy(connection->errorStr, output);
+               if (length >= sizeof(connection->errorStr))
+                       length = sizeof(connection->errorStr) - 1;
+
+               memcpy(connection->errorStr, output, length);
+               connection->errorStr[length] = 0;
                connection->error = MPD_ERROR_ACK;
                connection->errorCode = MPD_ACK_ERROR_UNK;
                connection->errorAt = MPD_ERROR_AT_UNK;
@@ -664,9 +667,8 @@ static void mpd_getNextReturnElement(mpd_Connection * connection) {
                connection->returnElement = mpd_newReturnElement(name,&(value[1]));
        }
        else {
-               snprintf(connection->errorStr,MPD_BUFFER_MAX_LENGTH,
+               snprintf(connection->errorStr, sizeof(connection->errorStr),
                         "error parsing: %s:%s",name,value);
-               connection->errorStr[MPD_BUFFER_MAX_LENGTH] = '\0';
                connection->error = 1;
        }
 }

diff --git a/src/libmpdclient.h b/src/libmpdclient.h
index e91013b9c1f4e37518c1672de86674ee11748864..c4a22b2d83ed643c3f181ad91ddd156d2a422218 100644 (file)
--- a/src/libmpdclient.h
+++ b/src/libmpdclient.h
@@ -110,7 +110,7 @@ typedef struct _mpd_Connection {
        /* use this to check the version of mpd */
        int version[3];
        /* IMPORTANT, you want to get the error messages from here */
-       char errorStr[MPD_BUFFER_MAX_LENGTH+1];
+       char errorStr[512];
        int errorCode;
        int errorAt;
        /* this will be set to MPD_ERROR_* if there is an error, 0 if not */