Code Conventions

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Code conventions

Function naming

All functions are named accordingly : module name (in lower case) + _ + function name (in mixed case, without underscores). For instance : intf_FooFunction. Static functions don't need usage of the module name.

Variable naming

Hungarian notations are used, that means we have the following prefixes :

   * i_ for integers (sometimes l_ for long integers) ;
   * b_ for booleans ;
   * d_ for doubles (sometimes f_ for floats) ;
   * pf_ for function pointers ;
   * psz_ for a Pointer to a String terminated by a Zero (C-string) ;
   * More generally, we add a p when the variable is a pointer to a type. 

If one variable has no basic type (for instance a complex structure), don't put any prefix (except p_* if it's a pointer). After one prefix, put an explicit variable name in lower case. If several words are required, join them with an underscore (no mixed case). Examples :

   * data_packet_t * p_buffer;
   * char psz_msg_date[42];
   * int pi_es_refcount[MAX_ES];
   * void (* pf_next_data_packet)( int * ); 

A few words about white spaces

First, never use tabs in the source (you're entitled to use them in the Makefile :-). Use set expandtab under vim or the equivalent under emacs. Indents are 4 spaces long.

Second, put spaces before and after operators, and inside brackets. For instance :

for( i = 0; i < 12; i++, j += 42 ); 

Third, leave braces alone on their lines (GNU style). For instance :

if( i_es == 42 )
   p_buffer[0] = 0x12;

We write C, so use C-style comments /* ... */.