| /* |
| * trace_seq.c |
| * |
| * Copyright (C) 2009 Red Hat Inc, Steven Rostedt <srostedt@redhat.com> |
| * |
| */ |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <stdarg.h> |
| |
| #include "parse-events.h" |
| |
| /** |
| * trace_seq_printf - sequence printing of trace information |
| * @s: trace sequence descriptor |
| * @fmt: printf format string |
| * |
| * It returns 0 if the trace oversizes the buffer's free |
| * space, 1 otherwise. |
| * |
| * The tracer may use either sequence operations or its own |
| * copy to user routines. To simplify formating of a trace |
| * trace_seq_printf is used to store strings into a special |
| * buffer (@s). Then the output may be either used by |
| * the sequencer or pulled into another buffer. |
| */ |
| int |
| trace_seq_printf(struct trace_seq *s, const char *fmt, ...) |
| { |
| int len = (TRACE_SEQ_SIZE - 1) - s->len; |
| va_list ap; |
| int ret; |
| |
| if (s->full || !len) |
| return 0; |
| |
| va_start(ap, fmt); |
| ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
| va_end(ap); |
| |
| /* If we can't write it all, don't bother writing anything */ |
| if (ret >= len) { |
| s->full = 1; |
| return 0; |
| } |
| |
| s->len += ret; |
| |
| return 1; |
| } |
| |
| /** |
| * trace_seq_vprintf - sequence printing of trace information |
| * @s: trace sequence descriptor |
| * @fmt: printf format string |
| * |
| * The tracer may use either sequence operations or its own |
| * copy to user routines. To simplify formating of a trace |
| * trace_seq_printf is used to store strings into a special |
| * buffer (@s). Then the output may be either used by |
| * the sequencer or pulled into another buffer. |
| */ |
| int |
| trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args) |
| { |
| int len = (TRACE_SEQ_SIZE - 1) - s->len; |
| int ret; |
| |
| if (s->full || !len) |
| return 0; |
| |
| ret = vsnprintf(s->buffer + s->len, len, fmt, args); |
| |
| /* If we can't write it all, don't bother writing anything */ |
| if (ret >= len) { |
| s->full = 1; |
| return 0; |
| } |
| |
| s->len += ret; |
| |
| return len; |
| } |
| |
| /** |
| * trace_seq_puts - trace sequence printing of simple string |
| * @s: trace sequence descriptor |
| * @str: simple string to record |
| * |
| * The tracer may use either the sequence operations or its own |
| * copy to user routines. This function records a simple string |
| * into a special buffer (@s) for later retrieval by a sequencer |
| * or other mechanism. |
| */ |
| int trace_seq_puts(struct trace_seq *s, const char *str) |
| { |
| int len = strlen(str); |
| |
| if (s->full) |
| return 0; |
| |
| if (len > ((TRACE_SEQ_SIZE - 1) - s->len)) { |
| s->full = 1; |
| return 0; |
| } |
| |
| memcpy(s->buffer + s->len, str, len); |
| s->len += len; |
| |
| return len; |
| } |
| |
| int trace_seq_putc(struct trace_seq *s, unsigned char c) |
| { |
| if (s->full) |
| return 0; |
| |
| if (s->len >= (TRACE_SEQ_SIZE - 1)) { |
| s->full = 1; |
| return 0; |
| } |
| |
| s->buffer[s->len++] = c; |
| |
| return 1; |
| } |
| |
| int trace_seq_do_printf(struct trace_seq *s) |
| { |
| return printf("%.*s%s", s->len, s->buffer, |
| s->full ? "[truncated]" : ""); |
| } |