diff options
| -rw-r--r-- | common/printf.c | 32 | ||||
| -rw-r--r-- | include/printf.h | 27 |
2 files changed, 41 insertions, 18 deletions
diff --git a/common/printf.c b/common/printf.c index b356e0e58a..dad02ac4c7 100644 --- a/common/printf.c +++ b/common/printf.c @@ -13,6 +13,13 @@ static const char error_str[] = "ERROR"; #define MAX_FORMAT 1024 /* Maximum chars in a single format field */ +/** + * Convert a single digit to hex + * + * @param c Value of digit (0 - 0x0f) + * + * @return The corresponding ASCII character ('0' - 'f'). + */ static int hexdigit(int c) { return c > 9 ? (c + 'a' - 10) : (c + '0'); @@ -21,10 +28,11 @@ static int hexdigit(int c) int vfnprintf(int (*addchar)(void *context, int c), void *context, const char *format, va_list args) { + /* + * Longest uint64 in decimal = 20 + * longest uint32 in binary = 32 + */ char intbuf[34]; - /* Longest uint64 in decimal = 20 - * longest uint32 in binary = 32 - */ int dropped_chars = 0; int is_left; int pad_zero; @@ -185,8 +193,10 @@ int vfnprintf(int (*addchar)(void *context, int c), void *context, if (format == error_str) continue; /* Bad format specifier */ - /* Convert integer to string, starting at end of - * buffer and working backwards. */ + /* + * Convert integer to string, starting at end of + * buffer and working backwards. + */ vstr = intbuf + sizeof(intbuf) - 1; *(vstr) = '\0'; @@ -256,15 +266,19 @@ int vfnprintf(int (*addchar)(void *context, int c), void *context, return dropped_chars ? EC_ERROR_OVERFLOW : EC_SUCCESS; } - /* Context for snprintf() */ struct snprintf_context { char *str; int size; }; - -/* Add a character to the string */ +/** + * Add a character to the string context. + * + * @param context Context receiving character + * @param c Character to add + * @return 0 if character added, 1 if character dropped because no space. + */ static int snprintf_addchar(void *context, int c) { struct snprintf_context *ctx = (struct snprintf_context *)context; @@ -277,8 +291,6 @@ static int snprintf_addchar(void *context, int c) return 0; } - -/* Print formatted outut to a string */ int snprintf(char *str, int size, const char *format, ...) { struct snprintf_context ctx; diff --git a/include/printf.h b/include/printf.h index fdc80c2943..109fae4e2e 100644 --- a/include/printf.h +++ b/include/printf.h @@ -54,18 +54,29 @@ /** * Print formatted output to a function, like vfprintf() * - * addchar() will be called for every character to be printed, with the context - * pointer passed to vfnprintf(). addchar() should return 0 if the character - * was accepted or non-zero if the character was dropped due to overflow. - * - * Returns error if output was truncated. + * @param addchar Function to be called for each character added. + * Will be passed the same context passed to vfnprintf(), + * and the character to add. Should return 0 if the + * character was accepted or non-zero if the character + * was dropped due to overflow. + * @param context Context pointer to pass to addchar() + * @param format Format string (see above for acceptable formats) + * @param args Parameters + * @return EC_SUCCESS, or non-zero if output was truncated. */ int vfnprintf(int (*addchar)(void *context, int c), void *context, const char *format, va_list args); - -/* Print formatted outut to a string */ +/** + * Print formatted outut to a string. + * + * Guarantees null-termination if size!=0. + * + * @param str Destination string + * @param size Size of destination in bytes + * @param format Format string + * @return EC_SUCCESS, or non-zero if output was truncated. + */ int snprintf(char *str, int size, const char *format, ...); - #endif /* __CROS_EC_PRINTF_H */ |