[libc-commits] [libc] [libc] Match the names of BSD sys/queue.h member names (PR #82696)

Petr Hosek via libc-commits libc-commits at lists.llvm.org
Thu Feb 22 14:10:48 PST 2024


https://github.com/petrhosek created https://github.com/llvm/llvm-project/pull/82696

While these names are technically internal implemenetation detail, there's an existing code which relies on these details and using different names makes LLVM libc implementation incompatible. Since our goal is for LLVM libc to be a drop in replacement, use the same name as BSD sys/queue.h version.

>From 9227d48abce66bf85d856d207d2bb9ea98bace09 Mon Sep 17 00:00:00 2001
From: Petr Hosek <phosek at google.com>
Date: Thu, 22 Feb 2024 22:03:29 +0000
Subject: [PATCH] [libc] Match the names of BSD sys/queue.h member names

While these names are technically internal implemenetation detail,
there's an existing code which relies on these details and using
different names makes LLVM libc implementation incompatible. Since
our goal is for LLVM libc to be a drop in replacement, use the same
name as BSD sys/queue.h version.
---
 .../llvm-libc-macros/sys-queue-macros.h       | 52 +++++++++----------
 1 file changed, 26 insertions(+), 26 deletions(-)

diff --git a/libc/include/llvm-libc-macros/sys-queue-macros.h b/libc/include/llvm-libc-macros/sys-queue-macros.h
index 59e6a9a392c978..7da643cb725330 100644
--- a/libc/include/llvm-libc-macros/sys-queue-macros.h
+++ b/libc/include/llvm-libc-macros/sys-queue-macros.h
@@ -22,12 +22,12 @@
 
 #define SLIST_HEAD(name, type)                                                 \
   struct name {                                                                \
-    struct type *first;                                                        \
+    struct type *slh_first;                                                    \
   }
 
 #define SLIST_CLASS_HEAD(name, type)                                           \
   struct name {                                                                \
-    class type *first;                                                         \
+    class type *slh_first;                                                     \
   }
 
 #define SLIST_HEAD_INITIALIZER(head)                                           \
@@ -45,8 +45,8 @@
 
 // Singly-linked list access methods.
 
-#define SLIST_EMPTY(head) ((head)->first == NULL)
-#define SLIST_FIRST(head) ((head)->first)
+#define SLIST_EMPTY(head) ((head)->slh_first == NULL)
+#define SLIST_FIRST(head) ((head)->slh_first)
 #define SLIST_NEXT(elem, field) ((elem)->field.next)
 
 #define SLIST_FOREACH(var, head, field)                                        \
@@ -132,18 +132,18 @@
 
 #define STAILQ_HEAD(name, type)                                                \
   struct name {                                                                \
-    struct type *first;                                                        \
-    struct type **last;                                                        \
+    struct type *stqh_first;                                                   \
+    struct type **stqh_last;                                                   \
   }
 
 #define STAILQ_CLASS_HEAD(name, type)                                          \
   struct name {                                                                \
-    class type *first;                                                         \
-    class type **last;                                                         \
+    class type *stqh_first;                                                    \
+    class type **stqh_last;                                                    \
   }
 
 #define STAILQ_HEAD_INITIALIZER(head)                                          \
-  { NULL, &(head).first }
+  { NULL, &(head).stqh_first }
 
 #define STAILQ_ENTRY(type)                                                     \
   struct {                                                                     \
@@ -157,12 +157,12 @@
 
 // Singly-linked tail queue access methods.
 
-#define STAILQ_EMPTY(head) ((head)->first == NULL)
-#define STAILQ_FIRST(head) ((head)->first)
+#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL)
+#define STAILQ_FIRST(head) ((head)->stqh_first)
 #define STAILQ_LAST(head, type, field)                                         \
   (STAILQ_EMPTY(head)                                                          \
        ? NULL                                                                  \
-       : __containerof((head)->last, QUEUE_TYPEOF(type), field.next))
+       : __containerof((head)->stqh_last, QUEUE_TYPEOF(type), field.next))
 #define STAILQ_NEXT(elem, field) ((elem)->field.next)
 
 #define STAILQ_FOREACH(var, head, field)                                       \
@@ -187,8 +187,8 @@
 #define STAILQ_CONCAT(head1, head2, type, field)                               \
   do {                                                                         \
     if (!STAILQ_EMPTY(head2)) {                                                \
-      *(head1)->last = (head2)->first;                                         \
-      (head1)->last = (head2)->last;                                           \
+      *(head1)->stqh_last = (head2)->stqh_first;                               \
+      (head1)->stqh_last = (head2)->stqh_last;                                 \
       STAILQ_INIT(head2);                                                      \
     }                                                                          \
   } while (0)
@@ -196,28 +196,28 @@
 #define STAILQ_INIT(head)                                                      \
   do {                                                                         \
     STAILQ_FIRST(head) = NULL;                                                 \
-    (head)->last = &STAILQ_FIRST(head);                                        \
+    (head)->stqh_last = &STAILQ_FIRST(head);                                   \
   } while (0)
 
 #define STAILQ_INSERT_AFTER(head, listelem, elem, field)                       \
   do {                                                                         \
     if ((STAILQ_NEXT(elem, field) = STAILQ_NEXT(listelem, field)) == NULL)     \
-      (head)->last = &STAILQ_NEXT(elem, field);                                \
+      (head)->stqh_last = &STAILQ_NEXT(elem, field);                           \
     STAILQ_NEXT(listelem, field) = (elem);                                     \
   } while (0)
 
 #define STAILQ_INSERT_HEAD(head, elem, field)                                  \
   do {                                                                         \
     if ((STAILQ_NEXT(elem, field) = STAILQ_FIRST(head)) == NULL)               \
-      (head)->last = &STAILQ_NEXT(elem, field);                                \
+      (head)->stqh_last = &STAILQ_NEXT(elem, field);                           \
     STAILQ_FIRST(head) = (elem);                                               \
   } while (0)
 
 #define STAILQ_INSERT_TAIL(head, elem, field)                                  \
   do {                                                                         \
     STAILQ_NEXT(elem, field) = NULL;                                           \
-    *(head)->last = (elem);                                                    \
-    (head)->last = &STAILQ_NEXT(elem, field);                                  \
+    *(head)->stqh_last = (elem);                                               \
+    (head)->stqh_last = &STAILQ_NEXT(elem, field);                             \
   } while (0)
 
 #define STAILQ_REMOVE(head, elem, type, field)                                 \
@@ -236,27 +236,27 @@
   do {                                                                         \
     if ((STAILQ_NEXT(elem, field) =                                            \
              STAILQ_NEXT(STAILQ_NEXT(elem, field), field)) == NULL)            \
-      (head)->last = &STAILQ_NEXT(elem, field);                                \
+      (head)->stqh_last = &STAILQ_NEXT(elem, field);                           \
   } while (0)
 
 #define STAILQ_REMOVE_HEAD(head, field)                                        \
   do {                                                                         \
     if ((STAILQ_FIRST(head) = STAILQ_NEXT(STAILQ_FIRST(head), field)) == NULL) \
-      (head)->last = &STAILQ_FIRST(head);                                      \
+      (head)->stqh_last = &STAILQ_FIRST(head);                                 \
   } while (0)
 
 #define STAILQ_SWAP(head1, head2, type)                                        \
   do {                                                                         \
     QUEUE_TYPEOF(type) *first = STAILQ_FIRST(head1);                           \
-    QUEUE_TYPEOF(type) **last = (head1)->last;                                 \
+    QUEUE_TYPEOF(type) **last = (head1)->stqh_last;                            \
     STAILQ_FIRST(head1) = STAILQ_FIRST(head2);                                 \
-    (head1)->last = (head2)->last;                                             \
+    (head1)->stqh_last = (head2)->stqh_last;                                   \
     STAILQ_FIRST(head2) = first;                                               \
-    (head2)->last = last;                                                      \
+    (head2)->stqh_last = last;                                                 \
     if (STAILQ_EMPTY(head1))                                                   \
-      (head1)->last = &STAILQ_FIRST(head1);                                    \
+      (head1)->stqh_last = &STAILQ_FIRST(head1);                               \
     if (STAILQ_EMPTY(head2))                                                   \
-      (head2)->last = &STAILQ_FIRST(head2);                                    \
+      (head2)->stqh_last = &STAILQ_FIRST(head2);                               \
   } while (0)
 
 #endif // __LLVM_LIBC_MACROS_SYS_QUEUE_MACROS_H



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