GUACAMOLE-1931: Allow writing to existing typescript files.

src/protocols/kubernetes/kubernetes.c

@@ -275,7 +275,8 @@ void* guac_kubernetes_client_thread(void* data) {
         guac_terminal_create_typescript(kubernetes_client->term,
                 settings->typescript_path,
                 settings->typescript_name,
-                settings->create_typescript_path);
+                settings->create_typescript_path,
+                settings->typescript_write_existing);
     }
 
     /* Init libwebsockets context creation parameters */

src/protocols/kubernetes/settings.c

@@ -45,6 +45,7 @@ const char* GUAC_KUBERNETES_CLIENT_ARGS[] = {
     "typescript-path",
     "typescript-name",
     "create-typescript-path",
+    "typescript-write-existing",
     "recording-path",
     "recording-name",
     "recording-exclude-output",
@@ -167,6 +168,12 @@ enum KUBERNETES_ARGS_IDX {
      */
     IDX_CREATE_TYPESCRIPT_PATH,
 
+    /**
+     * Whether existing files should be appended to when creating a new
+     * typescript. Disabled by default.
+     */
+    IDX_TYPESCRIPT_WRITE_EXISTING,
+
     /**
      * The full absolute path to the directory in which screen recordings
      * should be written.
@@ -366,6 +373,11 @@ guac_kubernetes_settings* guac_kubernetes_parse_args(guac_user* user,
         guac_user_parse_args_boolean(user, GUAC_KUBERNETES_CLIENT_ARGS, argv,
                 IDX_CREATE_TYPESCRIPT_PATH, false);
 
+    /* Parse allow write existing file flag */
+    settings->typescript_write_existing =
+        guac_user_parse_args_boolean(user, GUAC_KUBERNETES_CLIENT_ARGS, argv,
+                IDX_TYPESCRIPT_WRITE_EXISTING, false);
+
     /* Read recording path */
     settings->recording_path =
         guac_user_parse_args_string(user, GUAC_KUBERNETES_CLIENT_ARGS, argv,

src/protocols/kubernetes/settings.h

@@ -191,6 +191,12 @@ typedef struct guac_kubernetes_settings {
      */
     bool create_typescript_path;
 
+    /**
+     * Whether existing files should be appended to when creating a new
+     * typescript. Disabled by default.
+     */
+    bool typescript_write_existing;
+
     /**
      * The path in which the screen recording should be saved, if enabled. If
      * no screen recording should be saved, this will be NULL.

src/protocols/ssh/settings.c

@@ -57,6 +57,7 @@ const char* GUAC_SSH_CLIENT_ARGS[] = {
     "typescript-path",
     "typescript-name",
     "create-typescript-path",
+    "typescript-write-existing",
     "recording-path",
     "recording-name",
     "recording-exclude-output",
@@ -198,6 +199,12 @@ enum SSH_ARGS_IDX {
      */
     IDX_CREATE_TYPESCRIPT_PATH,
 
+    /**
+     * Whether existing files should be appended to when creating a new
+     * typescript. Disabled by default.
+     */
+    IDX_TYPESCRIPT_WRITE_EXISTING,
+
     /**
      * The full absolute path to the directory in which screen recordings
      * should be written.
@@ -472,6 +479,11 @@ guac_ssh_settings* guac_ssh_parse_args(guac_user* user,
         guac_user_parse_args_boolean(user, GUAC_SSH_CLIENT_ARGS, argv,
                 IDX_CREATE_TYPESCRIPT_PATH, false);
 
+    /* Parse allow write existing file flag */
+    settings->typescript_write_existing =
+        guac_user_parse_args_boolean(user, GUAC_SSH_CLIENT_ARGS, argv,
+                IDX_TYPESCRIPT_WRITE_EXISTING, false);
+
     /* Read recording path */
     settings->recording_path =
         guac_user_parse_args_string(user, GUAC_SSH_CLIENT_ARGS, argv,

src/protocols/ssh/settings.h

@@ -208,6 +208,12 @@ typedef struct guac_ssh_settings {
      */
     bool create_typescript_path;
 
+    /**
+     * Whether existing files should be appended to when creating a new
+     * typescript. Disabled by default.
+     */
+    bool typescript_write_existing;
+
     /**
      * The path in which the screen recording should be saved, if enabled. If
      * no screen recording should be saved, this will be NULL.

src/protocols/ssh/ssh.c

@@ -301,7 +301,8 @@ void* ssh_client_thread(void* data) {
         guac_terminal_create_typescript(ssh_client->term,
                 settings->typescript_path,
                 settings->typescript_name,
-                settings->create_typescript_path);
+                settings->create_typescript_path,
+                settings->typescript_write_existing);
     }
 
     /* Get user and credentials */

src/protocols/telnet/settings.c

@@ -49,6 +49,7 @@ const char* GUAC_TELNET_CLIENT_ARGS[] = {
     "typescript-path",
     "typescript-name",
     "create-typescript-path",
+    "typescript-write-existing",
     "recording-path",
     "recording-name",
     "recording-exclude-output",
@@ -150,6 +151,12 @@ enum TELNET_ARGS_IDX {
      */
     IDX_CREATE_TYPESCRIPT_PATH,
 
+    /**
+     * Whether existing files should be appended to when creating a new
+     * typescript. Disabled by default.
+     */
+    IDX_TYPESCRIPT_WRITE_EXISTING,
+
     /**
      * The full absolute path to the directory in which screen recordings
      * should be written.
@@ -463,6 +470,11 @@ guac_telnet_settings* guac_telnet_parse_args(guac_user* user,
         guac_user_parse_args_boolean(user, GUAC_TELNET_CLIENT_ARGS, argv,
                 IDX_CREATE_TYPESCRIPT_PATH, false);
 
+    /* Parse allow write existing file flag */
+    settings->typescript_write_existing =
+        guac_user_parse_args_boolean(user, GUAC_TELNET_CLIENT_ARGS, argv,
+                IDX_TYPESCRIPT_WRITE_EXISTING, false);
+
     /* Read recording path */
     settings->recording_path =
         guac_user_parse_args_string(user, GUAC_TELNET_CLIENT_ARGS, argv,

src/protocols/telnet/settings.h

@@ -196,6 +196,12 @@ typedef struct guac_telnet_settings {
      */
     bool create_typescript_path;
 
+    /**
+     * Whether existing files should be appended to when creating a new
+     * typescript. Disabled by default.
+     */
+    bool typescript_write_existing;
+
     /**
      * The path in which the screen recording should be saved, if enabled. If
      * no screen recording should be saved, this will be NULL.

src/protocols/telnet/telnet.c

@@ -644,7 +644,8 @@ void* guac_telnet_client_thread(void* data) {
         guac_terminal_create_typescript(telnet_client->term,
                 settings->typescript_path,
                 settings->typescript_name,
-                settings->create_typescript_path);
+                settings->create_typescript_path,
+                settings->typescript_write_existing);
     }
 
     /* Open telnet session */

src/terminal/terminal.c

@@ -2029,10 +2029,11 @@ void guac_terminal_pipe_stream_close(guac_terminal* term) {
 }
 
 int guac_terminal_create_typescript(guac_terminal* term, const char* path,
-        const char* name, int create_path) {
+        const char* name, int create_path, int allow_write_existing) {
 
     /* Create typescript */
-    term->typescript = guac_terminal_typescript_alloc(path, name, create_path);
+    term->typescript = guac_terminal_typescript_alloc(
+            path, name, create_path, allow_write_existing);
 
     /* Log failure */
     if (term->typescript == NULL) {

src/terminal/terminal/terminal.h

@@ -747,13 +747,18 @@ void guac_terminal_clipboard_append(guac_terminal* terminal,
 void guac_terminal_remove_user(guac_terminal* terminal, guac_user* user);
 
 /**
- * Requests that the terminal write all output to a new pair of typescript
- * files within the given path and using the given base name. Terminal output
- * will be written to these new files, along with timing information. If the
- * create_path flag is non-zero, the given path will be created if it does not
- * yet exist. If creation of the typescript files or path fails, error messages
- * will automatically be logged, and no typescript will be written. The
- * typescript will automatically be closed once the terminal is freed.
+ * Requests that the terminal write all output to a pair of typescript
+ * files within the given path and using the given base name. If
+ * allow_write_existing is non-zero, these may be existing files; otherwise,
+ * the existing files may not be written to, and a non-zero value will be
+ * returned.
+ *
+ * Terminal output will be written to the files, along with timing information.
+ * If the create_path flag is non-zero, the given path will be created if it
+ * does not yet exist. If creation of the typescript files or path fails,
+ * error messages will automatically be logged, and no typescript will be
+ * written. The typescript will automatically be closed once the terminal is
+ * freed.
  *
  * @param term
  *     The terminal whose output should be written to a typescript.
@@ -771,12 +776,16 @@ void guac_terminal_remove_user(guac_terminal* terminal, guac_user* user);
  *     written, or non-zero if the path should be created if it does not yet
  *     exist.
  *
+ * @param allow_write_existing
+ *     Non-zero if writing to existing files should be allowed, or zero
+ *     otherwise.
+ *
  * @return
  *     Zero if the typescript files have been successfully created and a
  *     typescript will be written, non-zero otherwise.
  */
 int guac_terminal_create_typescript(guac_terminal* term, const char* path,
-        const char* name, int create_path);
+        const char* name, int create_path, int allow_write_existing);
 
 /**
  * Immediately applies the given color scheme to the given terminal, overriding

src/terminal/terminal/typescript.h

@@ -125,11 +125,13 @@ typedef struct guac_terminal_typescript {
 } guac_terminal_typescript;
 
 /**
- * Creates a new pair of typescript files within the given path and using the
+ * Creates a pair of typescript files within the given path and using the
  * given base name, returning an abstraction which represents those files.
- * Terminal output will be written to these new files, along with timing
+ * Terminal output will be written to these files, along with timing
  * information. If the create_path flag is non-zero, the given path will be
- * created if it does not yet exist.
+ * created if it does not yet exist. If allow_write_existing is non-zero,
+ * these may be existing files; otherwise, any existing file will cause this
+ * function to fail, returning NULL.
  *
  * @param path
  *     The full absolute path to a directory in which the typescript files
@@ -144,12 +146,16 @@ typedef struct guac_terminal_typescript {
  *     written, or non-zero if the path should be created if it does not yet
  *     exist.
  *
+ * @param allow_write_existing
+ *     Non-zero if writing to existing files should be allowed, or zero
+ *     otherwise.
+ *
  * @return
  *     A new guac_terminal_typescript representing the typescript files
  *     requested, or NULL if creation of the typescript files failed.
  */
 guac_terminal_typescript* guac_terminal_typescript_alloc(const char* path,
-        const char* name, int create_path);
+        const char* name, int create_path, int allow_write_existing);
 
 /**
  * Writes a single byte of terminal data to the typescript, flushing and

src/terminal/typescript.c

@@ -33,12 +33,12 @@
 #include <fcntl.h>
 
 /**
- * Attempts to open a new typescript data file within the given path and having
- * the given name. If such a file already exists, sequential numeric suffixes
- * (.1, .2, .3, etc.) are appended until a filename is found which does not
- * exist (or until the maximum number of numeric suffixes has been tried). If
- * the file absolutely cannot be opened due to an error, -1 is returned and
- * errno is set appropriately.
+ * Attempts to open a typescript data file within the given path and having
+ * the given name. If such a file already exists and allow_write_existing is
+ * zero, sequential numeric suffixes (.1, .2, .3, etc.) are appended until a
+ * filename is found which does not exist (or until the maximum number of
+ * numeric suffixes has been tried). If the file absolutely cannot be opened
+ * due to an error, -1 is returned and errno is set appropriately.
  *
  * @param path
  *     The full path to the directory in which the data file should be created.
@@ -55,12 +55,17 @@
  * @param basename_size
  *     The number of bytes available within the provided basename buffer.
  *
+ * @param allow_write_existing
+ *     Non-zero if writing to an existing file should be allowed, or zero
+ *     otherwise.
+ *
  * @return
  *     The file descriptor of the open data file if open succeeded, or -1 on
  *     failure.
  */
 static int guac_terminal_typescript_open_data_file(const char* path,
-        const char* name, char* basename, int basename_size) {
+        const char* name, char* basename, int basename_size,
+        int allow_write_existing) {
 
     int i;
 
@@ -76,10 +81,11 @@ static int guac_terminal_typescript_open_data_file(const char* path,
         return -1;
     }
 
+    /* Require the file not exist already if allow_write_existing not set */
+    int file_flags = O_CREAT | O_WRONLY | (allow_write_existing ? 0 : O_EXCL);
+
     /* Attempt to open typescript data file */
-    int data_fd = open(basename,
-            O_CREAT | O_EXCL | O_WRONLY,
-            S_IRUSR | S_IWUSR | S_IRGRP);
+    int data_fd = open(basename, file_flags, S_IRUSR | S_IWUSR | S_IRGRP);
 
     /* Continuously retry with alternate names on failure */
     if (data_fd == -1) {
@@ -96,9 +102,7 @@ static int guac_terminal_typescript_open_data_file(const char* path,
             sprintf(suffix, "%i", i);
 
             /* Retry with newly-suffixed filename */
-            data_fd = open(basename,
-                    O_CREAT | O_EXCL | O_WRONLY,
-                    S_IRUSR | S_IWUSR | S_IRGRP);
+            data_fd = open(basename, file_flags, S_IRUSR | S_IWUSR | S_IRGRP);
 
         }
 
@@ -109,7 +113,7 @@ static int guac_terminal_typescript_open_data_file(const char* path,
 }
 
 guac_terminal_typescript* guac_terminal_typescript_alloc(const char* path,
-        const char* name, int create_path) {
+        const char* name, int create_path, int allow_write_existing) {
 
     /* Create path if it does not exist, fail if impossible */
     if (create_path && mkdir(path, S_IRWXU | S_IRGRP | S_IXGRP)
@@ -124,7 +128,8 @@ guac_terminal_typescript* guac_terminal_typescript_alloc(const char* path,
     typescript->data_fd = guac_terminal_typescript_open_data_file(
             path, name, typescript->data_filename,
             sizeof(typescript->data_filename)
-                - sizeof(GUAC_TERMINAL_TYPESCRIPT_TIMING_SUFFIX));
+                - sizeof(GUAC_TERMINAL_TYPESCRIPT_TIMING_SUFFIX),
+            allow_write_existing);
     if (typescript->data_fd == -1) {
         guac_mem_free(typescript);
         return NULL;
@@ -139,10 +144,12 @@ guac_terminal_typescript* guac_terminal_typescript_alloc(const char* path,
         return NULL;
     }
 
+    /* Require the file not exist already if allow_write_existing not set */
+    int file_flags = O_CREAT | O_WRONLY | (allow_write_existing ? 0 : O_EXCL);
+
     /* Attempt to open typescript timing file */
     typescript->timing_fd = open(typescript->timing_filename,
-            O_CREAT | O_EXCL | O_WRONLY,
-            S_IRUSR | S_IWUSR | S_IRGRP);
+            file_flags, S_IRUSR | S_IWUSR | S_IRGRP);
     if (typescript->timing_fd == -1) {
         close(typescript->data_fd);
         guac_mem_free(typescript);