I have the following piece of code (kernel code to be more specific) :
static int is_sram_locked(void)
{
if (OMAP2_DEVICE_TYPE_GP == omap_type()) {
/* RAMFW: R/W access to all initiators for all qualifier sets */
if (cpu_is_omap242x()) {
__raw_writel(0xFF, OMAP24XX_VA_REQINFOPERM0); /* all q-vects */
__raw_writel(0xCFDE, OMAP24XX_VA_READPERM0); /* all i-read */
__raw_writel(0xCFDE, OMAP24XX_VA_WRITEPERM0); /* all i-write */
}
if (cpu_is_omap34xx() && !cpu_is_am33xx()) {
__raw_writel(0xFFFF, OMAP34XX_VA_REQINFOPERM0); /* all q-vects */
__raw_writel(0xFFFF, OMAP34XX_VA_READPERM0); /* all i-read */
__raw_writel(0xFFFF, OMAP34XX_VA_WRITEPERM0); /* all i-write */
__raw_writel(0x0, OMAP34XX_VA_ADDR_MATCH2);
__raw_writel(0xFFFFFFFF, OMAP34XX_VA_SMS_RG_ATT0);
}
return 0;
} else
return 1; /* assume locked with no PPA or security driver */
}
This is copy-pasted from sublime 3, and as the title states, I get the following compilation error :
error: stray '\302' in program
error: stray '\273' in program
On lines that start with __raw_writel( ... )
I have done research about the problem and I found out that this error tells me that there is an unprintable character on the line in cause.
'\302 \273' is UTF-8 code for '»' (RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK)
I read that this problem often appears when you copy-paste code from somewhere else and those unprintable characters may have skipped your attention or your keyboard has a different layout that types strange characters. I inspected the code very closely and I could not find any of those foreign characters.
My big question is how can kernel code that I have never touched can present such errors ? And I have more than one file that comes with this error, which brings me to the fact that there might be something else wrong.
I have figured it out that I get this error on lines that start with anything else but a letter such as : '_' and '.' (these are the examples that rise issues for me so far)
Solutions I have tried :
Re-writing the entire lines;
Copy-paste the code into many UTF-8 unprintable character filters so I can find the 'stray' characters
Unicode Character Highlighter sublime packages
Note: I'm also using vim as editor and my .vimrc puts '»' as TABS and '·' as SPACES but only for indentation purposes, not as actual characters. I've fixed some similar errors when I copy-pasted from vim and those characters were actually in text, I deleted the characters and it got fixed. But for this I can't identify any 'stray' characters present in the code.
I'm out of ideas I can try to get over this so I'm asking for your help.
The macros were the problem. They referred to some macros I modified with some copy-paste code and completely forgot about it.
Special thanks to all.
Related
Good afternoon, I'm facing a problem on my c code and I don't know what is causing it.
Every time I try to print characters like these: "┌──┐" my program simply prints some strange characters, like on this screenshot:
I'm using Qt Creator on Windows, with Qt version 5.5.0 MSVC 64 bits. The compiler is the Microsoft Visual C++ Compiler 12.0 (amd64).
I tried changing the locale but with no success. The only way I found to print these characters was to define them as int variables with the ASCII code and printing them, but it led to some really extensive and ugly coding, like this:
int cSupEsq = 218; //'┌'
int cSupDir = 191; //'┐'
int cInfEsq = 192; //'└'
int cInfDir = 217; //'┘'
int mVert = 179; //'│'
int mHor = 196; //'─'
int espaco = 255; //' '
int letraO = 111; //'o'
//Inicia limpando a tela da aplicação
clrscr();
//Linha 1
printf("%c", cSupEsq);
for (i = 1; i < 79; i++) { printf("%c", mHor); }
printf("%c", cSupDir);
Is there any way I can make the program treat these characters correctly? What could be causing this problem?
Your solution to use the OEM code points is the right way to go, codepage 850/437 is the default code page for the console and therefore should work. You could also use SetConsoleOutputCP to ensure the correct code page is used for the console.
Having said that, what is happening when you do not use your workaround is that the source file is being saved using a different codepage ie. not codepage 850/437. The in memory representation of the source code is Unicode (probably UTF-8), when you save the file the in memory representation of the characters are mapped to the target code page for the file.
What you can do is to save the file using the 850/437 codepage as the target, I don't know how you do this in Qt Creator (If you can at all), in Visual Studio for example you can select the down arrow on the Save button and select "Save with encoding", you can then proceed to select the target codepage, in your case code page 850. This will ensure that the in memory code points are mapped correctly to the file to be compiled.
I hope that helps explain the issue.
It shouldn't be necessary to print the characters one at a time. Instead, you can use an escape sequence:
printf("\xDA\xBF\xC0\xD9\xB3\xC4\xFF");
I have the below code snippet which executes a script through C program.
char upgrd_bb[512] = "";
sprintf(upgrd_bb,"/usr/bin/./\UPGRD_BB_ALL '%s'", path_argv[5]);
if(!(system(upgrd_bb)))
{
dw_flag = 0;
printf("Unable to Upgrade BB ");
}
During Cross-compilation i get error
/home/ubuntu/Documents/FileOper.c:829:14: warning: universal character names are only valid in C++ and C99
/home/ubuntu/Documents/FileOper.c:829:14: error: incomplete universal character name \U
make: *** [/home/ubuntu/Documents/FileOper.o] Error 1
If i am changing the name of the script to any other character it compiles fine. can any one focus on this.
thanks in advance !!
In the string
"/usr/bin/./\UPGRD_BB_ALL '%s'"
You have the sequence \U, which is being treated as a Unicode escape sequence. If you delete the extra backslash to get
"/usr/bin/./UPGRD_BB_ALL '%s'"
then you should be all set.
On the other hand, if you need the extra backslash in the name, then escape it:
"/usr/bin/./\\UPGRD_BB_ALL '%s'"
Hope this helps!
Goal:
Find if a string contains a blank line. Whether it be '\n\n',
'\r\n\r\n', '\r\n\n', '\n\r\n'
Issues:
I don't think my current regex for finding '\n\n' is right. This is my first time really using regex outside of simple use of * when removing files in command line.
Is it possible to check for all of these cases (listed above) in one regex? or do I have to do 4 seperate calls to compile_regex?
Code:
int checkForBlankLine(char *reader) {
regex_t r;
compile_regex(&r, "*\n\n");
match_regex(&r, reader);
return 0;
}
void compile_regex(regex_t *r, char *matchText) {
int status;
regcomp(r, matchText, 0);
}
int match_regex(regex_t *r, char *reader) {
regmatch_t match[1];
int nomatch = regexec(r, reader, 1, match, 0);
if (nomatch) {
printf("No matches.\n");
} else {
printf("MATCH!\n");
}
return 0;
}
Notes:
I only need to worry about finding one blank line, that's why my regmatch_t match[1] is only one item long
reader is the char array containing the text I am checking for a blank line.
I have seen other examples and tried to base the code off of those examples, but I still seem to be missing something.
Thank you kindly for the help/advice.
If anything needs to be clarified please let me know.
It seems that you have to compile the regex as extended:
regcomp(&re, "\r?\n\r?\n", REG_EXTENDED);
The first atom, \r? is probably unnecessary, because it doesn't add to the blank-line condition if you don't capture the result.
In the above, blank line really means empty line. If you want blank line to mean a line that has no characters except for white space, you can use:
regcomp(&re, "\r?\n[ \t]*\r?\n", REG_EXTENDED);
(I don't think you can use the space character pattern, \s here instead of [ \t], because that would include carriage return and new-line.)
As others have already hinted at, the "simple use of * in the command line` is not a regular expression. This wildcard-matching is called file globbing and has different semantics.
Check what the * in a regex means. It's not like the wildcard "anything" in the command line. The * means that the previous component can appear any amount of times. The wildcard in regex is the .. So if you want to say match anything you can do .*, which would be anything, any amount of times.
So in your case you can do .*\n\n.* which would match anything that has \n\n.
Finally, you can use or in a regex and ( ) to group stuff. So you can do something like .*(\n\n|\r\n\r\n).* And that would match anything that has a \n\n or a \r\n\r\n.
Hope that helps.
Rather than looking for only \r or \n, look for not \r or \n?
Your regex would simply be
'[^\r\n]'
and a match result of false indicates a blank line to your specification.
I'm attempting to write a function that will pull text from different sources (Ethernet client/Serial/etc.) into a single line, then compare them and run other functions based on them. Simple..
And while this works, I am having issues when trying to call a simple Serial.println() from a function OTHER than loop().
So far, I have around 140 lines of code, but here's a trimmed down version of the portion that's causing me problems:
boolean fileTerm;
setup() {
fileTerm = false;
}
loop() {
char character;
String content="";
while (Serial.available()) {
character = Serial.read();
content.concat(character);
delay(1);
}
if (content != "") {
Serial.println("> " + content);
/** Error from Serial command string.
* 0 = No error
* 1 = Invalid command
*/
int err = testInput(content);
}
int testInput(String content) {
if (content == "term") {
fileTerm = true;
Serial.println("Starting Terminal Mode");
return 0;
}
if (content == "exit" && fileTerm == true) {
fileTerm = false;
Serial.println("Exiting Terminal Mode");
return 0;
}
return 1;
}
(full source at http://pastebin.com/prEuBaRJ)
So the point is to catch the "term" command and enter some sort of filesystem terminal mode (eventually to access and manipulate files on the SD card). The "exit" command will leave the terminal mode.
However, whenever I actually compile and type these commands with others into the Serial monitor, I see:
> hello
> term
> test for index.html
> exit
> test
> foo
> etc...
I figure the function is catching those reserved terms and actually processing them properly, but for whatever reason, is not sending the desired responses over the Serial bus.
Just for the sake of proper syntax, I am also declaring the testInput() function in a separate header, though I would doubt this has any bearing on whether or not this particular error would occur.
Any explainable reason for this?
Thanks.
Model: Arduino Uno R3, IDE version: 1.0.4, though this behavior also happened on v1.0.5 in some instances..
It is kinda guessable how you ended up putting delay(1) in your code, that was a workaround for a bug in your code. But you didn't solve it properly. What you probably saw was that your code was too eager to process the command, before you were done typing it. So you slowed it down.
But that wasn't the right fix, what you really want to do is wait for the entire command to be typed. Until you press the Enter key on your keyboard.
Which is the bug in your code right now, the content variable doesn't just contain "term", it also contains the character that was generated by your terminal's Enter key. Which is why you don't get a match.
So fix your code, add a test to check that you got the Enter key character. And then process the command.
From the Bison Manual:
In a simple interactive command parser
where each input is one line, it may
be sufficient to allow yyparse to
return 1 on error and have the caller
ignore the rest of the input line when
that happens (and then call yyparse
again).
This is pretty much what I want, but I am having trouble getting to work. Basically, I want to detect and error in flex, and if an error is detected, have Bison discard the entire line. What I have right now, isn't working quite right because my commands still get executed:
kbsh: ls '/home
Error: Unterminated Single Quote
admin kbrandt tempuser
syntax error
kbsh:
In my Bison file:
commands:
/*Empty*/ { prompt(); } |
command { prompt(); }
;
command:
error {return 1; } |
chdir_command |
pwd_command |
exit_command |
WORD arg_list {
execute_command($1, $2);
//printf("%s, %s\n", $1, $2);
} |
WORD { execute_command($1, NULL); }
;
And in my Flex:
' {BEGIN inQuote; }
<inQuote>\n {printf("Error: Unterminated Single Quote\n"); BEGIN(0); return(ERROR);}
I don't think you'll find a simple solution to handling these types of parsing errors in the lexer.
I would keep the lexer (flex/lex) as dumb as possible, it should just provide a stream of basic tokens (identifiers, keywords, etc...) and have the parser (yacc/bison) do the error detection. In fact it is setup for exactly what you want, with a little restructuring of your approach...
In the lexer (parser.l), keep it simple (no eol/newline handling), something like (isn't full thing):
}%
/* I don't recall if the backslashify is required below */
SINGLE_QUOTE_STRING \'.*\'
DOUBLE_QUOTE_STRING \".*\"
%%
{SINGLE_QUOTE_STRING} {
yylval.charstr = copy_to_tmp_buffer(yytext); // implies a %union
return STRING;
}
{DOUBLE_QUOTE_STRING} {
yylval.charstr = copy_to_tmp_buffer(yytext); // implies a %union
return STRING;
}
\n return NEWLINE;
Then in your parser.y file do all the real handling (isn't full thing):
command:
error NEWLINE
{ yyclearin; yyerrorok; print_the_next_command_prompt(); }
| chdir_command STRING NEWLINE
{ do_the_chdir($<charstr>2); print_the_next_command_prompt(); }
| ... and so on ...
There are two things to note here:
The shift of things like NEWLINE to the yacc side so that you can determine when the user is done with the command then you can clear things out and start over (assuming you have "int yywrap() {return 1;}" somewhere). If you try to detect it too early in flex, when do you know to raise an error?
chdir isn't one command (unless it was sub ruled and you just didn't show it), it now has chdir_command STRING (the argument to the chdir). This makes it so that the parser can figure out what went wrong, you can then yyerror if that directory doesn't exist, etc...
This way you should get something like (guessing what chdir might look like):
cd 'some_directory
syntax error
cd 'some_directory'
you are in the some_directory dude!
And it is all handled by the yacc grammer, not by the tokenizer.
I have found that keeping flex as simple as possible gives you the most ***flex***ibility. :)