| Message ID | 20200602115331.1659-4-filip.bozuta@syrmia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add strace support for printing arguments of selected syscalls | expand |
Le 02/06/2020 à 13:53, Filip Bozuta a écrit : > From: Filip Bozuta <Filip.Bozuta@syrmia.com> > > This patch implements strace argument printing functionality for syscall: > > *lseek - reposition read/write file offset > > off_t lseek(int fd, off_t offset, int whence) > man page: https://www.man7.org/linux/man-pages/man2/lseek.2.html > > Implementation notes: > > The syscall's third argument "whence" has predefined values: > "SEEK_SET","SEEK_CUR","SEEK_END","SEEK_DATA","SEEK_HOLE" > and thus a separate printing function "print_lseek" was stated > in file "strace.list". This function is defined in "strace.c" > by using an existing function "print_raw_param()" to print > the first and second argument and a switch(case) statement > for the predefined values of the third argument. > Values "SEEK_DATA" and "SEEK_HOLE" are defined in kernel version 3.1. > That is the reason why case statements for these values are > enwrapped in #ifdef directive. > > Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com> > --- > linux-user/strace.c | 32 ++++++++++++++++++++++++++++++++ > linux-user/strace.list | 2 +- > 2 files changed, 33 insertions(+), 1 deletion(-) > > diff --git a/linux-user/strace.c b/linux-user/strace.c > index 5cf419989c..b7f012f1b5 100644 > --- a/linux-user/strace.c > +++ b/linux-user/strace.c > @@ -1768,6 +1768,38 @@ print__llseek(const struct syscallname *name, > } > #endif > > +#ifdef TARGET_NR_lseek > +static void > +print_lseek(const struct syscallname *name, > + abi_long arg0, abi_long arg1, abi_long arg2, > + abi_long arg3, abi_long arg4, abi_long arg5) > +{ > + print_syscall_prologue(name); > + print_raw_param("%d", arg0, 0); > + print_raw_param("%ld", arg1, 0); TARGET_ABI_FMT_ld is better than "%ld", because abi_long can be a 32bit or a 64bit value, and be different between host and target. > + switch (arg2) { > + case SEEK_SET: > + qemu_log("SEEK_SET"); break; > + case SEEK_CUR: > + qemu_log("SEEK_CUR"); break; > + case SEEK_END: > + qemu_log("SEEK_END"); break; > +#ifdef SEEK_DATA > + case SEEK_DATA: > + qemu_log("SEEK_DATA"); break; > +#endif > +#ifdef SEEK_HOLE > + case SEEK_HOLE: > + qemu_log("SEEK_HOLE"); break; > +#endif > + default: > + print_raw_param("%#x", arg2, 1); > + qemu_log(" /* SEEK_??? */"); remove this line ^^^ > + } > + print_syscall_epilogue(name); > +} > +#endif > + > #if defined(TARGET_NR_socket) > static void > print_socket(const struct syscallname *name, > diff --git a/linux-user/strace.list b/linux-user/strace.list > index 8d51c54bca..5a56212532 100644 > --- a/linux-user/strace.list > +++ b/linux-user/strace.list > @@ -513,7 +513,7 @@ > { TARGET_NR_lremovexattr, "lremovexattr" , NULL, NULL, NULL }, > #endif > #ifdef TARGET_NR_lseek > -{ TARGET_NR_lseek, "lseek" , NULL, NULL, NULL }, > +{ TARGET_NR_lseek, "lseek" , NULL, print_lseek, NULL }, > #endif > #ifdef TARGET_NR_lsetxattr > { TARGET_NR_lsetxattr, "lsetxattr" , NULL, NULL, NULL }, > Thanks, Laurent
diff --git a/linux-user/strace.c b/linux-user/strace.c index 5cf419989c..b7f012f1b5 100644 --- a/linux-user/strace.c +++ b/linux-user/strace.c @@ -1768,6 +1768,38 @@ print__llseek(const struct syscallname *name, } #endif +#ifdef TARGET_NR_lseek +static void +print_lseek(const struct syscallname *name, + abi_long arg0, abi_long arg1, abi_long arg2, + abi_long arg3, abi_long arg4, abi_long arg5) +{ + print_syscall_prologue(name); + print_raw_param("%d", arg0, 0); + print_raw_param("%ld", arg1, 0); + switch (arg2) { + case SEEK_SET: + qemu_log("SEEK_SET"); break; + case SEEK_CUR: + qemu_log("SEEK_CUR"); break; + case SEEK_END: + qemu_log("SEEK_END"); break; +#ifdef SEEK_DATA + case SEEK_DATA: + qemu_log("SEEK_DATA"); break; +#endif +#ifdef SEEK_HOLE + case SEEK_HOLE: + qemu_log("SEEK_HOLE"); break; +#endif + default: + print_raw_param("%#x", arg2, 1); + qemu_log(" /* SEEK_??? */"); + } + print_syscall_epilogue(name); +} +#endif + #if defined(TARGET_NR_socket) static void print_socket(const struct syscallname *name, diff --git a/linux-user/strace.list b/linux-user/strace.list index 8d51c54bca..5a56212532 100644 --- a/linux-user/strace.list +++ b/linux-user/strace.list @@ -513,7 +513,7 @@ { TARGET_NR_lremovexattr, "lremovexattr" , NULL, NULL, NULL }, #endif #ifdef TARGET_NR_lseek -{ TARGET_NR_lseek, "lseek" , NULL, NULL, NULL }, +{ TARGET_NR_lseek, "lseek" , NULL, print_lseek, NULL }, #endif #ifdef TARGET_NR_lsetxattr { TARGET_NR_lsetxattr, "lsetxattr" , NULL, NULL, NULL },