[Feature] %ft file text tags add prefix search

%ft(filename,search_text)
finds a line beginning with search_text strips search_text and returns
the remainder of the line

Change-Id: I06fe029b89aa60e4dbf34c039d180c75213519a4

apps/gui/skin_engine/skin_parser.c

@@ -1343,14 +1343,30 @@ static int parse_filetext(struct skin_element *element,
     (void)wps_data;
     const char* filename;
     char buf[MAX_PATH];
+    char *buf_start = buf;
     int fd;
     int line = 0;
+    const char *search_text = NULL;
+    int search_len = 0;
 
-    /* format: %ft(filename[,line]) */
+    /* format: %ft(filename[,line|search text]) */
     filename = get_param_text(element, 0);
 
     if (element->params_count == 2)
-        line = get_param(element, 1)->data.number;
+    {
+        struct skin_tag_parameter *param1 = get_param(element, 1);
+        if (param1->type == INTEGER)
+            line = param1->data.number;
+        else if (param1->type == STRING)
+        {
+            search_text = get_param_text(element, 1);
+            line = 0x3FF; /* 1k lines is a pretty large file */
+            search_len = strlen(search_text);
+            DEBUGF("%s: found search text %s\n", __func__, search_text);
+        }
+        else
+            return WPS_ERROR_INVALID_PARAM;
+    }
     else if (element->params_count != 1)
     {
         DEBUGF("%s(file, line): %s Error: param count %d\n",
@@ -1364,7 +1380,7 @@ static int parse_filetext(struct skin_element *element,
     path_append(buf, ROCKBOX_DIR, filename, sizeof(buf));
     DEBUGF("%s %s[%d]\n", __func__, buf, line);
 
-    if ((fd = open_utf8(buf, O_RDONLY)) < 0)
+    if (line > 0x3FF || (fd = open_utf8(buf, O_RDONLY)) < 0)
     {
         DEBUGF("%s: Error Opening %s\n", __func__, buf);
         goto failure;
@@ -1373,8 +1389,15 @@ static int parse_filetext(struct skin_element *element,
     int rd = 0;
     while (line >= 0)
     {
-        if ((rd = read_line(fd, buf, sizeof(buf))) < 0)
+        if ((rd = read_line(fd, buf, sizeof(buf))) <= 0)
             break;
+        if (search_text && strncasecmp(buf, search_text, search_len) == 0)
+        {
+            buf_start += search_len;
+            rd -= search_len;
+            DEBUGF("%s: found '%s' Reading '%s'\n", __func__, search_text, buf);
+            break;
+        }
         line--;
     }
 
@@ -1386,10 +1409,11 @@ static int parse_filetext(struct skin_element *element,
 
     if (element->is_conditional)
     {
+        buf_start = buf;
         rd = 1; /* just alloc enough for the conditional to work*/
     }
 
-    buf[rd] = '\0';
+    buf_start[rd] = '\0';
 
     char * skinbuf = skin_buffer_alloc(rd+1);
 
@@ -1399,7 +1423,7 @@ static int parse_filetext(struct skin_element *element,
         close(fd);
         return WPS_ERROR_INVALID_PARAM;
     }
-    strcpy(skinbuf, buf);
+    strcpy(skinbuf, buf_start);
     close(fd);
     token->value.data = PTRTOSKINOFFSET(skin_buffer, skinbuf);
     token->type = SKIN_TOKEN_STRING;

lib/skin_parser/tag_table.c

@@ -50,7 +50,7 @@ static const struct tag_info legal_tags[] =
     TAG(SKIN_TOKEN_FILE_SIZE,             "fs", "", SKIN_REFRESH_STATIC),
     TAG(SKIN_TOKEN_FILE_VBR,              "fv", "", SKIN_REFRESH_STATIC),
     TAG(SKIN_TOKEN_FILE_DIRECTORY,        "d"  , "I", SKIN_REFRESH_STATIC),
-    TAG(SKIN_TOKEN_FILE_TEXT,             "ft" , "F|i", SKIN_REFRESH_STATIC),
+    TAG(SKIN_TOKEN_FILE_TEXT,             "ft" , "F|[is]", SKIN_REFRESH_STATIC),
 
     TAG(SKIN_TOKEN_FILE_BITRATE,          "Fb", "", SKIN_REFRESH_STATIC),
     TAG(SKIN_TOKEN_FILE_CODEC,            "Fc", "", SKIN_REFRESH_STATIC),

manual/appendix/wps_tags.tex

@@ -758,18 +758,26 @@ a horizontal progressbar which doesn't fill and draws the image
 \end{description}
 
 \begin{tagmap}
-  \config{\%ft(filename [,line]} & Get a line of text from a file.\\
+  \config{\%ft(filename [,line|search_text]} & Get a line of text from a file.\\
 \end{tagmap}
     Use this tag to check for the existence of a file or read a line of text from a file.
     Checking if a file exists can be done with \%?(ft(filename)<Found|NotFound>
     similarly you can also check if a specific line exists with \%?(ft(filename, n)<Found|NotFound>
      where n is the desired line.
+    or supply search text and do a search (ignoring case) of the beginning of each line.
+    If found this prefix will be removed and the rest of the string returned to the end of line.
+     \%?(ft(filename, search_text)<Found|NotFound>
+
     Note: empty files or files that do not exist are ignored by the skin engine otherwise
 \begin{description}
     \item[filename] -- filename Note: files can only be found in \fname{/.rockbox} directory or one of its children.
             eg. \%ft(wps/file.txt) would refer to \fname{/.rockbox/wps/file.txt}
     \item[line] -- OPTIONAL, which line to grab, defaults to the first line.
-                    Note: lines must end  with CR or LF but may not exceed 320 characters
+                    Note: lines must end  with CR or LF but may not exceed 320 characters, Max 1023 lines
+    \item[search_text] -- OPTIONAL, instead of a line number find a line that begins with search_text.
+                    Note: search_text will be stripped from beginning of string quotes should not be included
+                     unless you want to search for a string containing them
+                     lines must end  with CR or LF but may not exceed 320 characters including search text.
 \end{description}
 
 \begin{tagmap}