1# checksrc 2 3This is the tool we use within the curl project to scan C source code and 4check that it adheres to our [Source Code Style guide](CODE_STYLE.md). 5 6## Usage 7 8 checksrc.pl [options] [file1] [file2] ... 9 10## Command line options 11 12`-W[file]` skip that file and excludes it from being checked. Helpful 13when, for example, one of the files is generated. 14 15`-D[dir]` directory name to prepend to file names when accessing them. 16 17`-h` shows the help output, that also lists all recognized warnings 18 19## What does checksrc warn for? 20 21checksrc does not check and verify the code against the entire style guide, 22but the script is instead an effort to detect the most common mistakes and 23syntax mistakes that contributors make before they get accustomed to our code 24style. Heck, many of us regulars do the mistakes too and this script helps us 25keep the code in shape. 26 27 checksrc.pl -h 28 29Lists how to use the script and it lists all existing warnings it has and 30problems it detects. At the time of this writing, the existing checksrc 31warnings are: 32 33- `ASSIGNWITHINCONDITION`: Assignment within a conditional expression. The 34 code style mandates the assignment to be done outside of it. 35 36- `ASTERISKNOSPACE`: A pointer was declared like `char* name` instead of the more 37 appropriate `char *name` style. The asterisk should sit next to the name. 38 39- `ASTERISKSPACE`: A pointer was declared like `char * name` instead of the 40 more appropriate `char *name` style. The asterisk should sit right next to 41 the name without a space in between. 42 43- `BADCOMMAND`: There's a bad !checksrc! instruction in the code. See the 44 **Ignore certain warnings** section below for details. 45 46- `BANNEDFUNC`: A banned function was used. The functions sprintf, vsprintf, 47 strcat, strncat, gets are **never** allowed in curl source code. 48 49- `BRACEELSE`: '} else' on the same line. The else is supposed to be on the 50 following line. 51 52- `BRACEPOS`: wrong position for an open brace (`{`). 53 54- `COMMANOSPACE`: a comma without following space 55 56- `COPYRIGHT`: the file is missing a copyright statement! 57 58- `CPPCOMMENTS`: `//` comment detected, that's not C89 compliant 59 60- `FOPENMODE`: `fopen()` needs a macro for the mode string, use it 61 62- `INDENTATION`: detected a wrong start column for code. Note that this 63 warning only checks some specific places and will certainly miss many bad 64 indentations. 65 66- `LONGLINE`: A line is longer than 79 columns. 67 68- `MULTISPACE`: Multiple spaces were found where only one should be used. 69 70- `NOSPACEEQUALS`: An equals sign was found without preceding space. We prefer 71 `a = 2` and *not* `a=2`. 72 73- `ONELINECONDITION`: do not put the conditional block on the same line as `if()` 74 75- `OPENCOMMENT`: File ended with a comment (`/*`) still "open". 76 77- `PARENBRACE`: `){` was used without sufficient space in between. 78 79- `RETURNNOSPACE`: `return` was used without space between the keyword and the 80 following value. 81 82- `SEMINOSPACE`: There was no space (or newline) following a semicolon. 83 84- `SIZEOFNOPAREN`: Found use of sizeof without parentheses. We prefer 85 `sizeof(int)` style. 86 87- `SNPRINTF` - Found use of `snprintf()`. Since we use an internal replacement 88 with a different return code etc, we prefer `msnprintf()`. 89 90- `SPACEAFTERPAREN`: there was a space after open parenthesis, `( text`. 91 92- `SPACEBEFORECLOSE`: there was a space before a close parenthesis, `text )`. 93 94- `SPACEBEFORECOMMA`: there was a space before a comma, `one , two`. 95 96- `SPACEBEFOREPAREN`: there was a space before an open parenthesis, `if (`, 97 where one was not expected 98 99- `SPACESEMICOLON`: there was a space before semicolon, ` ;`. 100 101- `TABS`: TAB characters are not allowed! 102 103- `TRAILINGSPACE`: Trailing whitespace on the line 104 105- `TYPEDEFSTRUCT`: we frown upon (most) typedefed structs 106 107- `UNUSEDIGNORE`: a checksrc inlined warning ignore was asked for but not used, 108 that's an ignore that should be removed or changed to get used. 109 110### Extended warnings 111 112Some warnings are quite computationally expensive to perform, so they are 113turned off by default. To enable these warnings, place a `.checksrc` file in 114the directory where they should be activated with commands to enable the 115warnings you are interested in. The format of the file is to enable one 116warning per line like so: `enable <EXTENDEDWARNING>` 117 118Currently there is one extended warning which can be enabled: 119 120- `COPYRIGHTYEAR`: the current changeset hasn't updated the copyright year in 121 the source file 122 123## Ignore certain warnings 124 125Due to the nature of the source code and the flaws of the checksrc tool, there 126is sometimes a need to ignore specific warnings. checksrc allows a few 127different ways to do this. 128 129### Inline ignore 130 131You can control what to ignore within a specific source file by providing 132instructions to checksrc in the source code itself. You need a magic marker 133that is `!checksrc!` followed by the instruction. The instruction can ask to 134ignore a specific warning N number of times or you ignore all of them until 135you mark the end of the ignored section. 136 137Inline ignores are only done for that single specific source code file. 138 139Example 140 141 /* !checksrc! disable LONGLINE all */ 142 143This will ignore the warning for overly long lines until it is re-enabled with: 144 145 /* !checksrc! enable LONGLINE */ 146 147If the enabling isn't performed before the end of the file, it will be enabled 148automatically for the next file. 149 150You can also opt to ignore just N violations so that if you have a single long 151line you just can't shorten and is agreed to be fine anyway: 152 153 /* !checksrc! disable LONGLINE 1 */ 154 155... and the warning for long lines will be enabled again automatically after 156it has ignored that single warning. The number `1` can of course be changed to 157any other integer number. It can be used to make sure only the exact intended 158instances are ignored and nothing extra. 159 160### Directory wide ignore patterns 161 162This is a method we've transitioned away from. Use inline ignores as far as 163possible. 164 165Make a `checksrc.skip` file in the directory of the source code with the 166false positive, and include the full offending line into this file. 167