[Spice-devel] [linux/vd-agent v1 1/7] device-info: remove g_list_length() on compare_addresses()
Victor Toso
victortoso at redhat.com
Fri Jul 12 09:12:36 UTC 2019
From: Victor Toso <me at victortoso.com>
The g_list_length() function does iterate over both lists to compare
its length. Considering that we use this to check for true/false and
we will iterate again on both lists, we can do so once.
This should also avoid covscan/clang warnings:
| spice-vdagent-0.19.0/src/vdagent/device-info.c:216:27: warning: Access to field 'data' results in a dereference of a null pointer (loaded from variable 'lb')
| # PciDevice *devb = lb->data;
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:397:5: note: Taking false branch
| # if (!user_pci_addr) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:407:22: note: Calling 'find_device_at_pci_address'
| # char *dev_path = find_device_at_pci_address(user_pci_addr, &vendor_id, &device_id);
| # ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:329:5: note: Taking true branch
| # g_return_val_if_fail(pci_addr != NULL, NULL);
| # ^
| /usr/include/glib-2.0/glib/gmessages.h:594:9: note: expanded from macro 'g_return_val_if_fail'
| # if G_LIKELY(expr) { } else \
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:385:43: note: expanded from macro 'G_LIKELY'
| ##define G_LIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR((expr)), 1))
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:379:4: note: expanded from macro '_G_BOOLEAN_EXPR'
| # if (expr) \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:329:5: note: Taking true branch
| /usr/include/glib-2.0/glib/gmessages.h:594:6: note: expanded from macro 'g_return_val_if_fail'
| # if G_LIKELY(expr) { } else \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:329:5: note: Loop condition is false. Exiting loop
| /usr/include/glib-2.0/glib/gmessages.h:593:40: note: expanded from macro 'g_return_val_if_fail'
| ##define g_return_val_if_fail(expr,val) G_STMT_START{ \
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:346:23: note: expanded from macro 'G_STMT_START'
| ##define G_STMT_START do
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:330:5: note: Taking true branch
| # g_return_val_if_fail(device_id != NULL, NULL);
| # ^
| /usr/include/glib-2.0/glib/gmessages.h:594:9: note: expanded from macro 'g_return_val_if_fail'
| # if G_LIKELY(expr) { } else \
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:385:43: note: expanded from macro 'G_LIKELY'
| ##define G_LIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR((expr)), 1))
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:379:4: note: expanded from macro '_G_BOOLEAN_EXPR'
| # if (expr) \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:330:5: note: Taking true branch
| /usr/include/glib-2.0/glib/gmessages.h:594:6: note: expanded from macro 'g_return_val_if_fail'
| # if G_LIKELY(expr) { } else \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:330:5: note: Loop condition is false. Exiting loop
| /usr/include/glib-2.0/glib/gmessages.h:593:40: note: expanded from macro 'g_return_val_if_fail'
| ##define g_return_val_if_fail(expr,val) G_STMT_START{ \
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:346:23: note: expanded from macro 'G_STMT_START'
| ##define G_STMT_START do
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:331:5: note: Taking true branch
| # g_return_val_if_fail(vendor_id != NULL, NULL);
| # ^
| /usr/include/glib-2.0/glib/gmessages.h:594:9: note: expanded from macro 'g_return_val_if_fail'
| # if G_LIKELY(expr) { } else \
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:385:43: note: expanded from macro 'G_LIKELY'
| ##define G_LIKELY(expr) (__builtin_expect (_G_BOOLEAN_EXPR((expr)), 1))
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:379:4: note: expanded from macro '_G_BOOLEAN_EXPR'
| # if (expr) \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:331:5: note: Taking true branch
| /usr/include/glib-2.0/glib/gmessages.h:594:6: note: expanded from macro 'g_return_val_if_fail'
| # if G_LIKELY(expr) { } else \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:331:5: note: Loop condition is false. Exiting loop
| /usr/include/glib-2.0/glib/gmessages.h:593:40: note: expanded from macro 'g_return_val_if_fail'
| ##define g_return_val_if_fail(expr,val) G_STMT_START{ \
| # ^
| /usr/include/glib-2.0/glib/gmacros.h:346:23: note: expanded from macro 'G_STMT_START'
| ##define G_STMT_START do
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:334:5: note: Loop condition is true. Entering loop body
| # for (int i = 0; i < 10; ++i) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:340:13: note: Assuming the condition is false
| # if (stat(dev_path, &buf) != 0) {
| # ^~~~~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:340:9: note: Taking false branch
| # if (stat(dev_path, &buf) != 0) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:355:13: note: Assuming the condition is false
| # if (realpath(sys_path, device_link) == NULL) {
| # ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:355:9: note: Taking false branch
| # if (realpath(sys_path, device_link) == NULL) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:361:36: note: Calling 'parse_pci_address_from_sysfs_path'
| # PciAddress *drm_pci_addr = parse_pci_address_from_sysfs_path(device_link);
| # ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:129:9: note: Assuming 'pos' is non-null
| # if (!pos) {
| # ^~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:129:5: note: Taking false branch
| # if (!pos) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:136:9: note: Assuming 'pos' is non-null
| # if (!pos) {
| # ^~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:136:5: note: Taking false branch
| # if (!pos) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:142:9: note: Assuming 'pos' is non-null
| # if (!pos) {
| # ^~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:142:5: note: Taking false branch
| # if (!pos) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:146:27: note: Calling 'pci_address_new'
| # PciAddress *address = pci_address_new();
| # ^~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:61:12: note: Taking false branch
| # return g_new0(PciAddress, 1);
| # ^
| /usr/include/glib-2.0/glib/gmem.h:279:42: note: expanded from macro 'g_new0'
| ##define g_new0(struct_type, n_structs) _G_NEW (struct_type, n_structs, malloc0)
| # ^
| /usr/include/glib-2.0/glib/gmem.h:211:4: note: expanded from macro '_G_NEW'
| # if (__s == 1) \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:61:12: note: Left side of '&&' is false
| /usr/include/glib-2.0/glib/gmem.h:279:42: note: expanded from macro 'g_new0'
| ##define g_new0(struct_type, n_structs) _G_NEW (struct_type, n_structs, malloc0)
| # ^
| /usr/include/glib-2.0/glib/gmem.h:213:40: note: expanded from macro '_G_NEW'
| # else if (__builtin_constant_p (__n) && \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:61:12: note: Null pointer value stored to field 'devices'
| # return g_new0(PciAddress, 1);
| # ^~~~~~~~~~~~~~~~~~~~~
| /usr/include/glib-2.0/glib/gmem.h:279:42: note: expanded from macro 'g_new0'
| ##define g_new0(struct_type, n_structs) _G_NEW (struct_type, n_structs, malloc0)
| # ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| /usr/include/glib-2.0/glib/gmem.h:217:12: note: expanded from macro '_G_NEW'
| # __p = g_##func##_n (__n, __s); \
| # ^~~~~~~~~~~~~~~~~~~~~~~
| <scratch space>:76:1: note: expanded from here
| #g_malloc0_n
| #^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:146:27: note: Returning from 'pci_address_new'
| # PciAddress *address = pci_address_new();
| # ^~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:149:5: note: Loop condition is true. Entering loop body
| # while (pos) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:150:26: note: Taking false branch
| # PciDevice *dev = g_new0(PciDevice, 1);
| # ^
| /usr/include/glib-2.0/glib/gmem.h:279:42: note: expanded from macro 'g_new0'
| ##define g_new0(struct_type, n_structs) _G_NEW (struct_type, n_structs, malloc0)
| # ^
| /usr/include/glib-2.0/glib/gmem.h:211:4: note: expanded from macro '_G_NEW'
| # if (__s == 1) \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:150:26: note: Left side of '&&' is false
| /usr/include/glib-2.0/glib/gmem.h:279:42: note: expanded from macro 'g_new0'
| ##define g_new0(struct_type, n_structs) _G_NEW (struct_type, n_structs, malloc0)
| # ^
| /usr/include/glib-2.0/glib/gmem.h:213:40: note: expanded from macro '_G_NEW'
| # else if (__builtin_constant_p (__n) && \
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:152:9: note: Taking true branch
| # if (!parse_pci_device(pos + 1, next, dev)) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:154:13: note: Execution continues on line 159
| # break;
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:361:36: note: Returning from 'parse_pci_address_from_sysfs_path'
| # PciAddress *drm_pci_addr = parse_pci_address_from_sysfs_path(device_link);
| # ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:362:9: note: Taking false branch
| # if (!drm_pci_addr) {
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:367:14: note: Calling 'compare_addresses'
| # if (!compare_addresses(pci_addr, drm_pci_addr)) {
| # ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:207:11: note: Assuming the condition is true
| # if (!(a->domain == b->domain
| # ^~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:207:11: note: Left side of '&&' is true
| spice-vdagent-0.19.0/src/vdagent/device-info.c:208:12: note: Assuming the condition is true
| # && g_list_length(a->devices) == g_list_length(b->devices))) {
| # ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:207:5: note: Taking false branch
| # if (!(a->domain == b->domain
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:212:35: note: 'lb' initialized to a null pointer value
| # for (GList *la = a->devices, *lb = b->devices;
| # ^~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:213:10: note: Assuming 'la' is not equal to NULL
| # la != NULL;
| # ^~~~~~~~~~
| spice-vdagent-0.19.0/src/vdagent/device-info.c:212:5: note: Loop condition is true. Entering loop body
| # for (GList *la = a->devices, *lb = b->devices;
| # ^
| spice-vdagent-0.19.0/src/vdagent/device-info.c:216:27: note: Access to field 'data' results in a dereference of a null pointer (loaded from variable 'lb')
| # PciDevice *devb = lb->data;
| # ^~
| # 214| la = la->next, lb = lb->next) {
| # 215| PciDevice *deva = la->data;
| # 216|-> PciDevice *devb = lb->data;
| # 217|
| # 218| if (deva->slot != devb->slot
Signed-off-by: Victor Toso <victortoso at redhat.com>
---
src/vdagent/device-info.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/src/vdagent/device-info.c b/src/vdagent/device-info.c
index 4983543..cb66438 100644
--- a/src/vdagent/device-info.c
+++ b/src/vdagent/device-info.c
@@ -204,14 +204,13 @@ static PciAddress* parse_pci_address_from_spice(char *input)
static bool compare_addresses(PciAddress *a, PciAddress *b)
{
// only check domain, slot, and function
- if (!(a->domain == b->domain
- && g_list_length(a->devices) == g_list_length(b->devices))) {
+ if (a->domain != b->domain) {
return false;
}
- for (GList *la = a->devices, *lb = b->devices;
- la != NULL;
- la = la->next, lb = lb->next) {
+ GList *la = a->devices;
+ GList *lb = b->devices;
+ while (la != NULL && lb != NULL) {
PciDevice *deva = la->data;
PciDevice *devb = lb->data;
@@ -220,7 +219,9 @@ static bool compare_addresses(PciAddress *a, PciAddress *b)
return false;
}
}
- return true;
+
+ /* True only if both have the same length */
+ return (la == NULL && lb == NULL);
}
// Connector type names from xorg modesetting driver
--
2.21.0
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