diff options
Diffstat (limited to 'lib/qfstring.h')
| -rw-r--r-- | lib/qfstring.h | 112 |
1 files changed, 89 insertions, 23 deletions
diff --git a/lib/qfstring.h b/lib/qfstring.h index c57bd4ea..f6eb1807 100644 --- a/lib/qfstring.h +++ b/lib/qfstring.h @@ -28,20 +28,31 @@ /*============================================================================== * These "qfstrings" address the issues of dealing with *fixed* length * strings, particularly where the string handling must be async-signal-safe. + * + * Are also used to support snprintf() style printing, but to one or more + * fixed length buffers. */ /* When initialised a qf_string is set: * - * str = start of string -- and this is never changed - * ptr = start of string -- this is moved as stuff is appended - * end = last possible position for terminating '\0' - * -- and this is never changed + * str = start of string -- and this is never changed + * ptr = start of string -- this is moved as stuff is appended + * end = end of string -- and this is never changed + * offset = number of characters left to omit -- used to collect a long + * string in more than one section + * overflow = number of characters that had to leave out, because string + * was too short. + * + * When filling the string, will work right up to the byte just before the + * end. Does not terminate the string -- that must be done explicitly. */ struct qf_str { - char* str ; /* start of string */ - char* ptr ; /* current position */ - char* end ; /* end of string */ + char* str ; /* start of string */ + char* ptr ; /* current position */ + char* end ; /* end of string */ + uint offset ; /* number of chars to omit */ + uint overflow ; /* number of excess chars */ } ; typedef struct qf_str qf_str_t[1] ; @@ -82,22 +93,26 @@ enum pf_flags * Functions */ -extern void qfs_init(qf_str qfs, char* str, size_t size) ; -extern void qfs_init_as_is(qf_str qfs, char* str, size_t size) ; +extern void qfs_init(qf_str qfs, char* str, uint size) ; +extern void qfs_init_offset(qf_str qfs, char* str, uint size, uint offset) ; +extern void qfs_reset_offset(qf_str qfs, uint offset) ; +extern void qfs_init_as_is(qf_str qfs, char* str, uint size) ; -extern void qfs_term(qf_str qfs, const char* src) ; +Inline uint qfs_overflow(qf_str qfs) ; +Inline uint qfs_term(qf_str qfs) ; +extern void qfs_term_string(qf_str qfs, const char* src, uint n) ; -Inline int qfs_len(qf_str qfs) ; +Inline uint qfs_len(qf_str qfs) ; Inline void* qfs_ptr(qf_str qfs) ; -Inline int qfs_left(qf_str qfs) ; +Inline uint qfs_left(qf_str qfs) ; extern void qfs_append(qf_str qfs, const char* src) ; -extern void qfs_append_n(qf_str qfs, const char* src, size_t n) ; +extern void qfs_append_n(qf_str qfs, const char* src, uint n) ; -extern void qfs_append_ch_x_n(qf_str qfs, char ch, size_t n) ; +extern void qfs_append_ch_x_n(qf_str qfs, char ch, uint n) ; extern void qfs_append_justified(qf_str qfs, const char* src, int width) ; extern void qfs_append_justified_n(qf_str qfs, const char* src, - size_t n, int width) ; + uint n, int width) ; extern void qfs_signed(qf_str qfs, intmax_t s_val, enum pf_flags flags, int width, int precision) ; @@ -106,25 +121,27 @@ extern void qfs_unsigned(qf_str qfs, uintmax_t u_val, enum pf_flags flags, extern void qfs_pointer(qf_str qfs, void* p_val, enum pf_flags flags, int width, int precision) ; -extern void qfs_printf(qf_str qfs, const char* format, ...) +extern uint qfs_printf(qf_str qfs, const char* format, ...) PRINTF_ATTRIBUTE(2, 3) ; -extern void qfs_vprintf(qf_str qfs, const char *format, va_list args) ; +extern uint qfs_vprintf(qf_str qfs, const char *format, va_list args) ; + +Inline uint qfs_strlen(const char* str) ; /*============================================================================== * The Inline functions. */ /*------------------------------------------------------------------------------ - * Current length of qf_str, not counting the terminating '\0'. + * Current length of qf_str. */ -Inline int +Inline uint qfs_len(qf_str qfs) { return qfs->ptr - qfs->str ; } ; /*------------------------------------------------------------------------------ - * Address of the terminating '\0'. + * Address for next byte -- assuming zero offset -- may be the end. */ Inline void* qfs_ptr(qf_str qfs) @@ -133,14 +150,63 @@ qfs_ptr(qf_str qfs) } ; /*------------------------------------------------------------------------------ - * Current space left in the qstr, given what has been reserved for terminating - * '\0' and any other reservation. + * Current space left in the qstr -- assuming zero offset. */ -Inline int +Inline uint qfs_left(qf_str qfs) { return qfs->end - qfs->ptr ; } ; +/*------------------------------------------------------------------------------ + * Did everything we put in the qfs, fit ?. + * + * Returns: number of chars that did *not* fit. + */ +Inline uint +qfs_overflow(qf_str qfs) +{ + return qfs->overflow ; +} ; + +/*------------------------------------------------------------------------------ + * Insert '\0' terminator -- overwrites the last byte, if required. + * + * Assumes the qfs is not zero length ! + * + * Returns: number of chars that did *not* fit (after using one for '\0'). + * + * NB: does not advance pointer -- so length does not include the '\0' + */ +Inline uint +qfs_term(qf_str qfs) +{ + if (qfs->ptr >= qfs->end) + { + assert((qfs->ptr == qfs->end) && (qfs->ptr > qfs->str)) ; + --qfs->ptr ; + ++qfs->overflow ; + } ; + + *qfs->ptr = '\0' ; + return qfs->overflow ; +} ; + +/*------------------------------------------------------------------------------ + * async-signal-safe strlen + */ +Inline uint +qfs_strlen(const char* str) +{ + const char* s ; + + s = str ; + + if (s != NULL) + while (*s != '\0') + ++s ; + + return s - str ; +} #endif /* _ZEBRA_QSTRING_H */ |