From 278bb609c79d9bc9d718fc1395bf4249f9cdd36a Mon Sep 17 00:00:00 2001 From: Alberto Bertogli Date: Mon, 15 Jun 2009 03:08:28 -0300 Subject: [PATCH 32/48] Add a new preload library to enable failure points before a program starts This patch adds a new preload library which allows the user to enable failure points and remote control (via environment variables) before a program starts. It can be used combined with the posix preload to simulate faults in the standard library functions. A shell script to make it easier to use will be added in future commits, along more documentation. Signed-off-by: Alberto Bertogli --- .gitignore | 2 + preload/Makefile | 20 +++++- preload/{posix => run}/Makefile | 24 ++----- preload/run/run.c | 129 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 154 insertions(+), 21 deletions(-) copy preload/{posix => run}/Makefile (53%) create mode 100644 preload/run/run.c diff --git a/.gitignore b/.gitignore index 39f12b9..fdfed27 100644 --- a/.gitignore +++ b/.gitignore @@ -9,4 +9,6 @@ preload/posix/*.o preload/posix/*.so preload/posix/modules/*.o preload/posix/modules/*.mod.c +preload/run/*.o +preload/run/*.so diff --git a/preload/Makefile b/preload/Makefile index 20698c7..a575d71 100644 --- a/preload/Makefile +++ b/preload/Makefile @@ -1,11 +1,11 @@ default: all -all: posix +all: posix run -install: posix_install +install: posix_install run_install -clean: posix_clean +clean: posix_clean run_clean posix: @@ -17,6 +17,18 @@ posix_clean: posix_install: $(MAKE) -C posix/ install +run: + $(MAKE) -C run/ -.PHONY: default clean install posix posix_clean posix_install +run_clean: + $(MAKE) -C run/ clean + +run_install: + $(MAKE) -C run/ install + + + +.PHONY: default clean install \ + posix posix_clean posix_install \ + run run_clean run_install diff --git a/preload/posix/Makefile b/preload/run/Makefile similarity index 53% copy from preload/posix/Makefile copy to preload/run/Makefile index 411f61d..7655a86 100644 --- a/preload/posix/Makefile +++ b/preload/run/Makefile @@ -15,43 +15,33 @@ endif PREFIX=/usr/local -GEN_C = $(addsuffix .c,$(wildcard modules/*.mod)) -GEN_OBJS = $(addsuffix .o,$(wildcard modules/*.mod)) -CUSTOM_OBJS = $(patsubst %.c,%.o,$(wildcard modules/*.custom.c)) -OBJS = codegen.o $(GEN_OBJS) $(CUSTOM_OBJS) +OBJS = run.o ifneq ($(V), 1) NICE_CC = @echo " CC $@"; $(CC) - NICE_GEN = @echo " GEN $@"; ./generate else NICE_CC = $(CC) - NICE_GEN = ./generate endif default: all -all: fiu_posix_preload.so - -$(GEN_OBJS): $(GEN_C) - -%.mod.c: %.mod - $(NICE_GEN) $< $@ +all: fiu_run_preload.so .c.o: $(NICE_CC) $(ALL_CFLAGS) -c $< -o $@ -fiu_posix_preload.so: $(OBJS) +fiu_run_preload.so: $(OBJS) $(NICE_CC) $(ALL_CFLAGS) -shared -fPIC $(OBJS) -lfiu -ldl \ - -o fiu_posix_preload.so + -o fiu_run_preload.so -install: fiu_posix_preload.so +install: fiu_run_preload.so install -d $(PREFIX)/lib - install -m 0755 fiu_posix_preload.so $(PREFIX)/lib + install -m 0755 fiu_run_preload.so $(PREFIX)/lib clean: - rm -f $(OBJS) $(GEN_OBJS:.o=.c) fiu_posix_preload.so + rm -f $(OBJS) fiu_run_preload.so rm -f *.bb *.bbg *.da *.gcov *.gcda *.gcno gmon.out .PHONY: default install clean diff --git a/preload/run/run.c b/preload/run/run.c new file mode 100644 index 0000000..cf0dfa6 --- /dev/null +++ b/preload/run/run.c @@ -0,0 +1,129 @@ + +#include /* printf() */ +#include /* execve() */ +#include /* strtok(), memset(), strncpy() */ +#include /* atoi(), atol() */ +#include /* getopt() */ + +#include +#include + +/* Maximum size of parameters to the enable options */ +#define MAX_ENOPT 128 + +enum fp_type { + FP_ALWAYS = 1, + FP_PROB = 2, +}; + +struct enable_option { + char buf[MAX_ENOPT]; + enum fp_type type; + char *name; + int failnum; + unsigned long failinfo; + float probability; +}; + +/* Fills the enopt structure taking the values from the given string, which is + * assumed to be in of the form: + * + * name,probability,failnum,failinfo + * + * All fields are optional, except for the name. On error, enopt->name will be + * set to NULL. Probability is in percent, -1 indicates it should always be + * enabled. */ +static void parse_enable(const char *s, struct enable_option *enopt) +{ + char *tok; + char *state; + + enopt->name = NULL; + enopt->type = FP_ALWAYS; + enopt->failnum = 1; + enopt->failinfo = 0; + enopt->probability = 1; + + memset(enopt->buf, 0, MAX_ENOPT); + strncpy(enopt->buf, s, MAX_ENOPT); + + tok = strtok_r(enopt->buf, ",", &state); + if (tok == NULL) + return; + enopt->name = tok; + + tok = strtok_r(NULL, ",", &state); + if (tok == NULL) + return; + if (atoi(tok) >= 0) { + enopt->type = FP_PROB; + enopt->probability = atof(tok) / 100.0; + } + + tok = strtok_r(NULL, ",", &state); + if (tok == NULL) + return; + enopt->failnum = atoi(tok); + + tok = strtok_r(NULL, ",", &state); + if (tok == NULL) + return; + enopt->failinfo = atol(tok); +} + +/* We set the constructor with priority 300 so it runs after the other + * libfiu preloaders (if they're enabled), which use the 200 range */ +static void __attribute__((constructor(300))) fiu_run_init(void) +{ + int r; + struct enable_option enopt; + char *fiu_enable_env, *fiu_enable_s, *fiu_fifo_env; + char *tok, *state; + + fiu_init(0); + + fiu_fifo_env = getenv("FIU_CTRL_FIFO"); + if (fiu_fifo_env != NULL && *fiu_fifo_env != '\0') + fiu_rc_fifo(fiu_fifo_env); + + fiu_enable_env = getenv("FIU_ENABLE"); + if (fiu_enable_env == NULL) + return; + + /* copy fiu_enable_env to fiu_enable_s so we can strtok() it */ + fiu_enable_s = malloc(strlen(fiu_enable_env) + 1); + strcpy(fiu_enable_s, fiu_enable_env); + + state = NULL; + tok = strtok_r(fiu_enable_s, ":", &state); + while (tok != NULL) { + parse_enable(tok, &enopt); + if (enopt.name == NULL) { + fprintf(stderr, "fiu-run.so: " + "ignoring enable without name"); + tok = strtok_r(NULL, ":", &state); + continue; + } + + if (enopt.type == FP_ALWAYS) { + r = fiu_enable(enopt.name, enopt.failnum, + (void *) enopt.failinfo, 0); + } else { + r = fiu_enable_random(enopt.name, enopt.failnum, + (void *) enopt.failinfo, 0, + enopt.probability); + } + + if (r < 0) { + fprintf(stderr, "fiu-run.so: " + "couldn't enable failure %s\n", + enopt.name); + continue; + } + + tok = strtok_r(NULL, ":", &state); + } + + free(fiu_enable_s); +} + -- 1.6.2.2.646.gb214