diff --git a/include/printk.h b/include/printk.h index b4ae0b3..4384fb8 100644 --- a/include/printk.h +++ b/include/printk.h @@ -120,4 +120,9 @@ void log_print(unsigned flags); +struct va_format { + const char *fmt; + va_list *va; +}; + #endif diff --git a/lib/vsprintf.c b/lib/vsprintf.c index fa9fb75..6fe0283 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -302,6 +302,11 @@ * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] * little endian output byte order is: * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] + * - 'V' For a struct va_format which contains a format string * and va_list *, + * call vsnprintf(->format, *->va_list). + * Implements a "recursive vsnprintf". + * Do not use this feature without some mechanism to verify the + * correctness of the format string and va_list arguments. * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives * (default assumed to be phys_addr_t, passed by reference) * @@ -318,6 +323,16 @@ if (IS_ENABLED(CONFIG_PRINTF_UUID)) return uuid_string(buf, end, ptr, field_width, precision, flags, fmt); break; + case 'V': + { + va_list va; + + va_copy(va, *((struct va_format *)ptr)->va); + buf += vsnprintf(buf, end > buf ? end - buf : 0, + ((struct va_format *)ptr)->fmt, va); + va_end(va); + return buf; + } case 'a': return address_val(buf, end, ptr, field_width, precision, flags, fmt); case 'I':