Overhaul the way programs are loaded at startup and exec() works. Now the
checking of programs done in these two places are combined, which avoids
duplicate code and greatly reduces the number of cases in which exec()
fails causing Valgrind to bomb out.
Also, we can now load some programs we could not previously, such as scripts
lacking a "#!" line at the start. Also, the startup failure messages for
bad programs match the shell's messages very closely.
And I added a whole bunch of regtests to test all this.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4918 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/m_main.c b/coregrind/m_main.c
index a76bc47..8727d7f 100644
--- a/coregrind/m_main.c
+++ b/coregrind/m_main.c
@@ -724,37 +724,56 @@
}
/* Need a static copy because can't use dynamic mem allocation yet */
-static HChar executable_name[VKI_PATH_MAX];
+static HChar executable_name_in [VKI_PATH_MAX];
+static HChar executable_name_out[VKI_PATH_MAX];
static Bool match_executable(const char *entry)
{
- HChar buf[VG_(strlen)(entry) + VG_(strlen)(executable_name) + 3];
+ HChar buf[VG_(strlen)(entry) + VG_(strlen)(executable_name_in) + 3];
- /* empty PATH element means . */
+ /* empty PATH element means '.' */
if (*entry == '\0')
entry = ".";
- VG_(snprintf)(buf, sizeof(buf), "%s/%s", entry, executable_name);
+ VG_(snprintf)(buf, sizeof(buf), "%s/%s", entry, executable_name_in);
+
+ // Don't match directories
+ if (VG_(is_dir)(buf))
+ return False;
+
+ // If we match an executable, we choose that immediately. If we find a
+ // matching non-executable we remember it but keep looking for an
+ // matching executable later in the path.
if (VG_(access)(buf, True/*r*/, False/*w*/, True/*x*/) == 0) {
- VG_(strncpy)( executable_name, buf, VKI_PATH_MAX-1 );
- executable_name[VKI_PATH_MAX-1] = 0;
- return True;
+ VG_(strncpy)( executable_name_out, buf, VKI_PATH_MAX-1 );
+ executable_name_out[VKI_PATH_MAX-1] = 0;
+ return True; // Stop looking
+ } else if (VG_(access)(buf, True/*r*/, False/*w*/, False/*x*/) == 0
+ && VG_STREQ(executable_name_out, ""))
+ {
+ VG_(strncpy)( executable_name_out, buf, VKI_PATH_MAX-1 );
+ executable_name_out[VKI_PATH_MAX-1] = 0;
+ return False; // Keep looking
+ } else {
+ return False; // Keep looking
}
- return False;
}
+// Returns NULL if it wasn't found.
static HChar* find_executable ( HChar* exec )
{
vg_assert(NULL != exec);
- VG_(strncpy)( executable_name, exec, VKI_PATH_MAX-1 );
- executable_name[VKI_PATH_MAX-1] = 0;
-
- if (VG_(strchr)(executable_name, '/') == NULL) {
- /* no '/' - we need to search the path */
+ if (VG_(strchr)(exec, '/')) {
+ // Has a '/' - use the name as is
+ VG_(strncpy)( executable_name_out, exec, VKI_PATH_MAX-1 );
+ } else {
+ // No '/' - we need to search the path
+ VG_(strncpy)( executable_name_in, exec, VKI_PATH_MAX-1 );
+ VG_(memset) ( executable_name_out, 0, VKI_PATH_MAX );
HChar *path = VG_(getenv)("PATH");
scan_colsep(path, match_executable);
}
- return executable_name;
+ return VG_STREQ(executable_name_out, "") ? NULL : executable_name_out;
}
@@ -802,27 +821,29 @@
static void load_client ( /*OUT*/struct exeinfo* info,
/*OUT*/Addr* client_eip)
{
- HChar* exec;
+ HChar* exe_name;
Int ret;
SysRes res;
vg_assert( VG_(args_the_exename) != NULL);
- exec = find_executable( VG_(args_the_exename) );
+ exe_name = find_executable( VG_(args_the_exename) );
+
+ if (!exe_name) {
+ VG_(printf)("valgrind: %s: command not found\n", VG_(args_the_exename));
+ VG_(exit)(127); // 127 is Posix NOTFOUND
+ }
VG_(memset)(info, 0, sizeof(*info));
info->exe_base = VG_(client_base);
info->exe_end = VG_(client_end);
- ret = VG_(do_exec)(exec, info);
- if (ret != 0) {
- VG_(printf)("valgrind: do_exec(%s) failed: %s\n",
- exec, VG_(strerror)(ret));
- VG_(exit)(127);
- }
+ ret = VG_(do_exec)(exe_name, info);
+
+ // The client was successfully loaded! Continue.
/* Get hold of a file descriptor which refers to the client
executable. This is needed for attaching to GDB. */
- res = VG_(open)(exec, VKI_O_RDONLY, VKI_S_IRUSR);
+ res = VG_(open)(exe_name, VKI_O_RDONLY, VKI_S_IRUSR);
if (!res.isError)
VG_(cl_exec_fd) = res.val;