[Qemu-devel] [PATCH v2 0/7] Code cleanup and minor fixes

[Qemu-devel] [PATCH v2 0/7] Code cleanup and minor fixes

[Jeff Cody]

Minor bug fixes and code cleanup.

Changes from v1 -> v2:

Rebased to v2.10.0

Jeff Cody (7):
  block/ssh: don't call libssh2_init() in block_init()
  block/ssh: make compliant with coding guidelines
  block/sheepdog: remove spurious NULL check
  block/sheepdog: code beautification
  block/curl: check error return of curl_global_init()
  block/curl: fix minor memory leaks
  block/curl: code cleanup to comply with coding style

 block/curl.c     | 124 +++++++++++++++++++++++------------------
 block/sheepdog.c | 164 +++++++++++++++++++++++++++----------------------------
 block/ssh.c      |  72 +++++++++++++++---------
 3 files changed, 199 insertions(+), 161 deletions(-)

-- 
2.9.5

[Qemu-devel] [PATCH v2 1/7] block/ssh: don't call libssh2_init() in block_init()

[Jeff Cody]

We don't need libssh2 failure to be fatal (we could just opt to not
register the driver on failure). But, it is probably a good idea to
avoid external library calls during the block_init(), and call the
libssh2 global init function on the first usage, returning any errors.

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/ssh.c | 40 +++++++++++++++++++++++++++++-----------
 1 file changed, 29 insertions(+), 11 deletions(-)

diff --git a/block/ssh.c b/block/ssh.c
index e8f0404..cbb0e34 100644
--- a/block/ssh.c
+++ b/block/ssh.c
@@ -83,12 +83,28 @@ typedef struct BDRVSSHState {
     bool unsafe_flush_warning;
 } BDRVSSHState;
 
-static void ssh_state_init(BDRVSSHState *s)
+static bool ssh_libinit_called;
+
+static int ssh_state_init(BDRVSSHState *s, Error **errp)
 {
+    int ret;
+
+    if (!ssh_libinit_called) {
+        ret = libssh2_init(0);
+        if (ret) {
+            error_setg(errp, "libssh2 initialization failed with %d", ret);
+            return ret;
+        }
+        ssh_libinit_called = true;
+    }
+
+
     memset(s, 0, sizeof *s);
     s->sock = -1;
     s->offset = -1;
     qemu_co_mutex_init(&s->lock);
+
+    return 0;
 }
 
 static void ssh_state_free(BDRVSSHState *s)
@@ -772,8 +788,13 @@ static int ssh_file_open(BlockDriverState *bs, QDict *options, int bdrv_flags,
     BDRVSSHState *s = bs->opaque;
     int ret;
     int ssh_flags;
+    Error *local_err = NULL;
 
-    ssh_state_init(s);
+    ret = ssh_state_init(s, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return ret;
+    }
 
     ssh_flags = LIBSSH2_FXF_READ;
     if (bdrv_flags & BDRV_O_RDWR) {
@@ -821,8 +842,13 @@ static int ssh_create(const char *filename, QemuOpts *opts, Error **errp)
     BDRVSSHState s;
     ssize_t r2;
     char c[1] = { '\0' };
+    Error *local_err = NULL;
 
-    ssh_state_init(&s);
+    ret = ssh_state_init(&s, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return ret;
+    }
 
     /* Get desired file size. */
     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
@@ -1213,14 +1239,6 @@ static BlockDriver bdrv_ssh = {
 
 static void bdrv_ssh_init(void)
 {
-    int r;
-
-    r = libssh2_init(0);
-    if (r != 0) {
-        fprintf(stderr, "libssh2 initialization failed, %d\n", r);
-        exit(EXIT_FAILURE);
-    }
-
     bdrv_register(&bdrv_ssh);
 }
 
-- 
2.9.5

[Qemu-devel] [PATCH v2 2/7] block/ssh: make compliant with coding guidelines

[Jeff Cody]

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/ssh.c | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/block/ssh.c b/block/ssh.c
index cbb0e34..97f7673 100644
--- a/block/ssh.c
+++ b/block/ssh.c
@@ -241,7 +241,7 @@ static int parse_uri(const char *filename, QDict *options, Error **errp)
         goto err;
     }
 
-    if(uri->user && strcmp(uri->user, "") != 0) {
+    if (uri->user && strcmp(uri->user, "") != 0) {
         qdict_put_str(options, "user", uri->user);
     }
 
@@ -268,7 +268,7 @@ static int parse_uri(const char *filename, QDict *options, Error **errp)
 
  err:
     if (uri) {
-      uri_free(uri);
+        uri_free(uri);
     }
     return -EINVAL;
 }
@@ -342,7 +342,7 @@ static int check_host_key_knownhosts(BDRVSSHState *s,
     libssh2_knownhost_readfile(knh, knh_file, LIBSSH2_KNOWNHOST_FILE_OPENSSH);
 
     r = libssh2_knownhost_checkp(knh, host, port, hostkey, len,
-                                 LIBSSH2_KNOWNHOST_TYPE_PLAIN|
+                                 LIBSSH2_KNOWNHOST_TYPE_PLAIN |
                                  LIBSSH2_KNOWNHOST_KEYENC_RAW,
                                  &found);
     switch (r) {
@@ -405,15 +405,18 @@ static int compare_fingerprint(const unsigned char *fingerprint, size_t len,
     unsigned c;
 
     while (len > 0) {
-        while (*host_key_check == ':')
+        while (*host_key_check == ':') {
             host_key_check++;
+        }
         if (!qemu_isxdigit(host_key_check[0]) ||
-            !qemu_isxdigit(host_key_check[1]))
+            !qemu_isxdigit(host_key_check[1])) {
             return 1;
+        }
         c = hex2decimal(host_key_check[0]) * 16 +
             hex2decimal(host_key_check[1]);
-        if (c - *fingerprint != 0)
+        if (c - *fingerprint != 0) {
             return c - *fingerprint;
+        }
         fingerprint++;
         len--;
         host_key_check += 2;
@@ -433,8 +436,8 @@ check_host_key_hash(BDRVSSHState *s, const char *hash,
         return -EINVAL;
     }
 
-    if(compare_fingerprint((unsigned char *) fingerprint, fingerprint_len,
-                           hash) != 0) {
+    if (compare_fingerprint((unsigned char *) fingerprint, fingerprint_len,
+                            hash) != 0) {
         error_setg(errp, "remote host key does not match host_key_check '%s'",
                    hash);
         return -EPERM;
@@ -507,7 +510,7 @@ static int authenticate(BDRVSSHState *s, const char *user, Error **errp)
         goto out;
     }
 
-    for(;;) {
+    for (;;) {
         r = libssh2_agent_get_identity(agent, &identity, prev_identity);
         if (r == 1) {           /* end of list */
             break;
@@ -863,8 +866,8 @@ static int ssh_create(const char *filename, QemuOpts *opts, Error **errp)
     }
 
     r = connect_to_ssh(&s, uri_options,
-                       LIBSSH2_FXF_READ|LIBSSH2_FXF_WRITE|
-                       LIBSSH2_FXF_CREAT|LIBSSH2_FXF_TRUNC,
+                       LIBSSH2_FXF_READ  | LIBSSH2_FXF_WRITE |
+                       LIBSSH2_FXF_CREAT | LIBSSH2_FXF_TRUNC,
                        0644, errp);
     if (r < 0) {
         ret = r;
@@ -872,7 +875,7 @@ static int ssh_create(const char *filename, QemuOpts *opts, Error **errp)
     }
 
     if (total_size > 0) {
-        libssh2_sftp_seek64(s.sftp_handle, total_size-1);
+        libssh2_sftp_seek64(s.sftp_handle, total_size - 1);
         r2 = libssh2_sftp_write(s.sftp_handle, c, 1);
         if (r2 < 0) {
             sftp_error_setg(errp, &s, "truncate failed");
@@ -1111,7 +1114,7 @@ static int ssh_write(BDRVSSHState *s, BlockDriverState *bs,
          * works for me.
          */
         if (r == 0) {
-            ssh_seek(s, offset + written, SSH_SEEK_WRITE|SSH_SEEK_FORCE);
+            ssh_seek(s, offset + written, SSH_SEEK_WRITE | SSH_SEEK_FORCE);
             co_yield(s, bs);
             goto again;
         }
@@ -1125,8 +1128,9 @@ static int ssh_write(BDRVSSHState *s, BlockDriverState *bs,
             end_of_vec = i->iov_base + i->iov_len;
         }
 
-        if (offset + written > s->attrs.filesize)
+        if (offset + written > s->attrs.filesize) {
             s->attrs.filesize = offset + written;
+        }
     }
 
     return 0;
-- 
2.9.5

[Qemu-devel] [PATCH v2 3/7] block/sheepdog: remove spurious NULL check

[Jeff Cody]

'tag' is already checked in the lines immediately preceding this check,
and set to non-NULL if NULL.  No need to check again, it hasn't changed.

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/sheepdog.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/sheepdog.c b/block/sheepdog.c
index abb2e79..bbbfa72 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -1632,7 +1632,7 @@ static int sd_open(BlockDriverState *bs, QDict *options, int flags,
     if (!tag) {
         tag = "";
     }
-    if (tag && strlen(tag) >= SD_MAX_VDI_TAG_LEN) {
+    if (strlen(tag) >= SD_MAX_VDI_TAG_LEN) {
         error_setg(errp, "value of parameter 'tag' is too long");
         ret = -EINVAL;
         goto err_no_fd;
-- 
2.9.5

[Qemu-devel] [PATCH v2 4/7] block/sheepdog: code beautification

[Jeff Cody]

No functional changes, just whitespace manipulation.

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/sheepdog.c | 162 +++++++++++++++++++++++++++----------------------------
 1 file changed, 81 insertions(+), 81 deletions(-)

diff --git a/block/sheepdog.c b/block/sheepdog.c
index bbbfa72..ad461f1 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -400,7 +400,7 @@ typedef struct BDRVSheepdogReopenState {
     int cache_flags;
 } BDRVSheepdogReopenState;
 
-static const char * sd_strerror(int err)
+static const char *sd_strerror(int err)
 {
     int i;
 
@@ -3078,111 +3078,111 @@ static QemuOptsList sd_create_opts = {
 };
 
 static BlockDriver bdrv_sheepdog = {
-    .format_name    = "sheepdog",
-    .protocol_name  = "sheepdog",
-    .instance_size  = sizeof(BDRVSheepdogState),
-    .bdrv_parse_filename    = sd_parse_filename,
-    .bdrv_file_open = sd_open,
-    .bdrv_reopen_prepare    = sd_reopen_prepare,
-    .bdrv_reopen_commit     = sd_reopen_commit,
-    .bdrv_reopen_abort      = sd_reopen_abort,
-    .bdrv_close     = sd_close,
-    .bdrv_create    = sd_create,
-    .bdrv_has_zero_init = bdrv_has_zero_init_1,
-    .bdrv_getlength = sd_getlength,
+    .format_name                  = "sheepdog",
+    .protocol_name                = "sheepdog",
+    .instance_size                = sizeof(BDRVSheepdogState),
+    .bdrv_parse_filename          = sd_parse_filename,
+    .bdrv_file_open               = sd_open,
+    .bdrv_reopen_prepare          = sd_reopen_prepare,
+    .bdrv_reopen_commit           = sd_reopen_commit,
+    .bdrv_reopen_abort            = sd_reopen_abort,
+    .bdrv_close                   = sd_close,
+    .bdrv_create                  = sd_create,
+    .bdrv_has_zero_init           = bdrv_has_zero_init_1,
+    .bdrv_getlength               = sd_getlength,
     .bdrv_get_allocated_file_size = sd_get_allocated_file_size,
-    .bdrv_truncate  = sd_truncate,
+    .bdrv_truncate                = sd_truncate,
 
-    .bdrv_co_readv  = sd_co_readv,
-    .bdrv_co_writev = sd_co_writev,
-    .bdrv_co_flush_to_disk  = sd_co_flush_to_disk,
-    .bdrv_co_pdiscard = sd_co_pdiscard,
-    .bdrv_co_get_block_status = sd_co_get_block_status,
+    .bdrv_co_readv                = sd_co_readv,
+    .bdrv_co_writev               = sd_co_writev,
+    .bdrv_co_flush_to_disk        = sd_co_flush_to_disk,
+    .bdrv_co_pdiscard             = sd_co_pdiscard,
+    .bdrv_co_get_block_status     = sd_co_get_block_status,
 
-    .bdrv_snapshot_create   = sd_snapshot_create,
-    .bdrv_snapshot_goto     = sd_snapshot_goto,
-    .bdrv_snapshot_delete   = sd_snapshot_delete,
-    .bdrv_snapshot_list     = sd_snapshot_list,
+    .bdrv_snapshot_create         = sd_snapshot_create,
+    .bdrv_snapshot_goto           = sd_snapshot_goto,
+    .bdrv_snapshot_delete         = sd_snapshot_delete,
+    .bdrv_snapshot_list           = sd_snapshot_list,
 
-    .bdrv_save_vmstate  = sd_save_vmstate,
-    .bdrv_load_vmstate  = sd_load_vmstate,
+    .bdrv_save_vmstate            = sd_save_vmstate,
+    .bdrv_load_vmstate            = sd_load_vmstate,
 
-    .bdrv_detach_aio_context = sd_detach_aio_context,
-    .bdrv_attach_aio_context = sd_attach_aio_context,
+    .bdrv_detach_aio_context      = sd_detach_aio_context,
+    .bdrv_attach_aio_context      = sd_attach_aio_context,
 
-    .create_opts    = &sd_create_opts,
+    .create_opts                  = &sd_create_opts,
 };
 
 static BlockDriver bdrv_sheepdog_tcp = {
-    .format_name    = "sheepdog",
-    .protocol_name  = "sheepdog+tcp",
-    .instance_size  = sizeof(BDRVSheepdogState),
-    .bdrv_parse_filename    = sd_parse_filename,
+    .format_name                  = "sheepdog",
+    .protocol_name                = "sheepdog+tcp",
+    .instance_size                = sizeof(BDRVSheepdogState),
+    .bdrv_parse_filename          = sd_parse_filename,
     .bdrv_file_open = sd_open,
-    .bdrv_reopen_prepare    = sd_reopen_prepare,
-    .bdrv_reopen_commit     = sd_reopen_commit,
-    .bdrv_reopen_abort      = sd_reopen_abort,
-    .bdrv_close     = sd_close,
-    .bdrv_create    = sd_create,
-    .bdrv_has_zero_init = bdrv_has_zero_init_1,
-    .bdrv_getlength = sd_getlength,
+    .bdrv_reopen_prepare          = sd_reopen_prepare,
+    .bdrv_reopen_commit           = sd_reopen_commit,
+    .bdrv_reopen_abort            = sd_reopen_abort,
+    .bdrv_close                   = sd_close,
+    .bdrv_create                  = sd_create,
+    .bdrv_has_zero_init           = bdrv_has_zero_init_1,
+    .bdrv_getlength               = sd_getlength,
     .bdrv_get_allocated_file_size = sd_get_allocated_file_size,
-    .bdrv_truncate  = sd_truncate,
+    .bdrv_truncate                = sd_truncate,
 
-    .bdrv_co_readv  = sd_co_readv,
-    .bdrv_co_writev = sd_co_writev,
-    .bdrv_co_flush_to_disk  = sd_co_flush_to_disk,
-    .bdrv_co_pdiscard = sd_co_pdiscard,
-    .bdrv_co_get_block_status = sd_co_get_block_status,
+    .bdrv_co_readv                = sd_co_readv,
+    .bdrv_co_writev               = sd_co_writev,
+    .bdrv_co_flush_to_disk        = sd_co_flush_to_disk,
+    .bdrv_co_pdiscard             = sd_co_pdiscard,
+    .bdrv_co_get_block_status     = sd_co_get_block_status,
 
-    .bdrv_snapshot_create   = sd_snapshot_create,
-    .bdrv_snapshot_goto     = sd_snapshot_goto,
-    .bdrv_snapshot_delete   = sd_snapshot_delete,
-    .bdrv_snapshot_list     = sd_snapshot_list,
+    .bdrv_snapshot_create         = sd_snapshot_create,
+    .bdrv_snapshot_goto           = sd_snapshot_goto,
+    .bdrv_snapshot_delete         = sd_snapshot_delete,
+    .bdrv_snapshot_list           = sd_snapshot_list,
 
-    .bdrv_save_vmstate  = sd_save_vmstate,
-    .bdrv_load_vmstate  = sd_load_vmstate,
+    .bdrv_save_vmstate            = sd_save_vmstate,
+    .bdrv_load_vmstate            = sd_load_vmstate,
 
-    .bdrv_detach_aio_context = sd_detach_aio_context,
-    .bdrv_attach_aio_context = sd_attach_aio_context,
+    .bdrv_detach_aio_context      = sd_detach_aio_context,
+    .bdrv_attach_aio_context      = sd_attach_aio_context,
 
-    .create_opts    = &sd_create_opts,
+    .create_opts                  = &sd_create_opts,
 };
 
 static BlockDriver bdrv_sheepdog_unix = {
-    .format_name    = "sheepdog",
-    .protocol_name  = "sheepdog+unix",
-    .instance_size  = sizeof(BDRVSheepdogState),
-    .bdrv_parse_filename    = sd_parse_filename,
-    .bdrv_file_open = sd_open,
-    .bdrv_reopen_prepare    = sd_reopen_prepare,
-    .bdrv_reopen_commit     = sd_reopen_commit,
-    .bdrv_reopen_abort      = sd_reopen_abort,
-    .bdrv_close     = sd_close,
-    .bdrv_create    = sd_create,
-    .bdrv_has_zero_init = bdrv_has_zero_init_1,
-    .bdrv_getlength = sd_getlength,
+    .format_name                  = "sheepdog",
+    .protocol_name                = "sheepdog+unix",
+    .instance_size                = sizeof(BDRVSheepdogState),
+    .bdrv_parse_filename          = sd_parse_filename,
+    .bdrv_file_open               = sd_open,
+    .bdrv_reopen_prepare          = sd_reopen_prepare,
+    .bdrv_reopen_commit           = sd_reopen_commit,
+    .bdrv_reopen_abort            = sd_reopen_abort,
+    .bdrv_close                   = sd_close,
+    .bdrv_create                  = sd_create,
+    .bdrv_has_zero_init           = bdrv_has_zero_init_1,
+    .bdrv_getlength               = sd_getlength,
     .bdrv_get_allocated_file_size = sd_get_allocated_file_size,
-    .bdrv_truncate  = sd_truncate,
+    .bdrv_truncate                = sd_truncate,
 
-    .bdrv_co_readv  = sd_co_readv,
-    .bdrv_co_writev = sd_co_writev,
-    .bdrv_co_flush_to_disk  = sd_co_flush_to_disk,
-    .bdrv_co_pdiscard = sd_co_pdiscard,
-    .bdrv_co_get_block_status = sd_co_get_block_status,
+    .bdrv_co_readv                = sd_co_readv,
+    .bdrv_co_writev               = sd_co_writev,
+    .bdrv_co_flush_to_disk        = sd_co_flush_to_disk,
+    .bdrv_co_pdiscard             = sd_co_pdiscard,
+    .bdrv_co_get_block_status     = sd_co_get_block_status,
 
-    .bdrv_snapshot_create   = sd_snapshot_create,
-    .bdrv_snapshot_goto     = sd_snapshot_goto,
-    .bdrv_snapshot_delete   = sd_snapshot_delete,
-    .bdrv_snapshot_list     = sd_snapshot_list,
+    .bdrv_snapshot_create         = sd_snapshot_create,
+    .bdrv_snapshot_goto           = sd_snapshot_goto,
+    .bdrv_snapshot_delete         = sd_snapshot_delete,
+    .bdrv_snapshot_list           = sd_snapshot_list,
 
-    .bdrv_save_vmstate  = sd_save_vmstate,
-    .bdrv_load_vmstate  = sd_load_vmstate,
+    .bdrv_save_vmstate            = sd_save_vmstate,
+    .bdrv_load_vmstate            = sd_load_vmstate,
 
-    .bdrv_detach_aio_context = sd_detach_aio_context,
-    .bdrv_attach_aio_context = sd_attach_aio_context,
+    .bdrv_detach_aio_context      = sd_detach_aio_context,
+    .bdrv_attach_aio_context      = sd_attach_aio_context,
 
-    .create_opts    = &sd_create_opts,
+    .create_opts                  = &sd_create_opts,
 };
 
 static void bdrv_sheepdog_init(void)
-- 
2.9.5

[Qemu-devel] [PATCH v2 5/7] block/curl: check error return of curl_global_init()

[Jeff Cody]

If curl_global_init() fails, per the documentation no other curl
functions may be called, so make sure to check the return value.

Also, some minor changes to the initialization latch variable 'inited':

- Make it static in the file, for clarity
- Change the name for clarity
- Make it a bool

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/curl.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/block/curl.c b/block/curl.c
index 2a244e2..00a9879 100644
--- a/block/curl.c
+++ b/block/curl.c
@@ -89,6 +89,8 @@ static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
 
 struct BDRVCURLState;
 
+static bool libcurl_initialized;
+
 typedef struct CURLAIOCB {
     Coroutine *co;
     QEMUIOVector *qiov;
@@ -686,14 +688,23 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
     double d;
     const char *secretid;
     const char *protocol_delimiter;
+    int ret;
 
-    static int inited = 0;
 
     if (flags & BDRV_O_RDWR) {
         error_setg(errp, "curl block device does not support writes");
         return -EROFS;
     }
 
+    if (!libcurl_initialized) {
+        ret = curl_global_init(CURL_GLOBAL_ALL);
+        if (ret) {
+            error_setg(errp, "libcurl initialization failed with %d", ret);
+            return -EIO;
+        }
+        libcurl_initialized = true;
+    }
+
     qemu_mutex_init(&s->mutex);
     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
     qemu_opts_absorb_qdict(opts, options, &local_err);
@@ -772,11 +783,6 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
         }
     }
 
-    if (!inited) {
-        curl_global_init(CURL_GLOBAL_ALL);
-        inited = 1;
-    }
-
     DPRINTF("CURL: Opening %s\n", file);
     QSIMPLEQ_INIT(&s->free_state_waitq);
     s->aio_context = bdrv_get_aio_context(bs);
-- 
2.9.5

[Qemu-devel] [PATCH v2 6/7] block/curl: fix minor memory leaks

[Jeff Cody]

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/curl.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/block/curl.c b/block/curl.c
index 00a9879..35cf417 100644
--- a/block/curl.c
+++ b/block/curl.c
@@ -857,6 +857,9 @@ out_noclean:
     qemu_mutex_destroy(&s->mutex);
     g_free(s->cookie);
     g_free(s->url);
+    g_free(s->username);
+    g_free(s->proxyusername);
+    g_free(s->proxypassword);
     qemu_opts_del(opts);
     return -EINVAL;
 }
@@ -955,6 +958,9 @@ static void curl_close(BlockDriverState *bs)
 
     g_free(s->cookie);
     g_free(s->url);
+    g_free(s->username);
+    g_free(s->proxyusername);
+    g_free(s->proxypassword);
 }
 
 static int64_t curl_getlength(BlockDriverState *bs)
-- 
2.9.5

[Qemu-devel] [PATCH v2 7/7] block/curl: code cleanup to comply with coding style

[Jeff Cody]

This addresses non-functional changes to help curl.c better comply
with the coding styles (comments, indentation, brackets, etc.).

One minor code change is the combination of two if statements into
a single if statement.

Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 block/curl.c | 100 +++++++++++++++++++++++++++++++----------------------------
 1 file changed, 52 insertions(+), 48 deletions(-)

diff --git a/block/curl.c b/block/curl.c
index 35cf417..c557b59 100644
--- a/block/curl.c
+++ b/block/curl.c
@@ -32,8 +32,10 @@
 #include <curl/curl.h>
 #include "qemu/cutils.h"
 
-// #define DEBUG_CURL
-// #define DEBUG_VERBOSE
+/*
+ #define DEBUG_CURL
+ #define DEBUG_VERBOSE
+*/
 
 #ifdef DEBUG_CURL
 #define DEBUG_CURL_PRINT 1
@@ -76,15 +78,15 @@ static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
 #define CURL_TIMEOUT_DEFAULT 5
 #define CURL_TIMEOUT_MAX 10000
 
-#define CURL_BLOCK_OPT_URL       "url"
-#define CURL_BLOCK_OPT_READAHEAD "readahead"
-#define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
-#define CURL_BLOCK_OPT_TIMEOUT "timeout"
-#define CURL_BLOCK_OPT_COOKIE    "cookie"
-#define CURL_BLOCK_OPT_COOKIE_SECRET "cookie-secret"
-#define CURL_BLOCK_OPT_USERNAME "username"
-#define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
-#define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
+#define CURL_BLOCK_OPT_URL                   "url"
+#define CURL_BLOCK_OPT_READAHEAD             "readahead"
+#define CURL_BLOCK_OPT_SSLVERIFY             "sslverify"
+#define CURL_BLOCK_OPT_TIMEOUT               "timeout"
+#define CURL_BLOCK_OPT_COOKIE                "cookie"
+#define CURL_BLOCK_OPT_COOKIE_SECRET         "cookie-secret"
+#define CURL_BLOCK_OPT_USERNAME              "username"
+#define CURL_BLOCK_OPT_PASSWORD_SECRET       "password-secret"
+#define CURL_BLOCK_OPT_PROXY_USERNAME        "proxy-username"
 #define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
 
 struct BDRVCURLState;
@@ -110,8 +112,7 @@ typedef struct CURLSocket {
     QLIST_ENTRY(CURLSocket) next;
 } CURLSocket;
 
-typedef struct CURLState
-{
+typedef struct CURLState {
     struct BDRVCURLState *s;
     CURLAIOCB *acb[CURL_NUM_ACB];
     CURL *curl;
@@ -196,22 +197,22 @@ static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
 
     DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, (int)fd);
     switch (action) {
-        case CURL_POLL_IN:
-            aio_set_fd_handler(s->aio_context, fd, false,
-                               curl_multi_read, NULL, NULL, state);
-            break;
-        case CURL_POLL_OUT:
-            aio_set_fd_handler(s->aio_context, fd, false,
-                               NULL, curl_multi_do, NULL, state);
-            break;
-        case CURL_POLL_INOUT:
-            aio_set_fd_handler(s->aio_context, fd, false,
-                               curl_multi_read, curl_multi_do, NULL, state);
-            break;
-        case CURL_POLL_REMOVE:
-            aio_set_fd_handler(s->aio_context, fd, false,
-                               NULL, NULL, NULL, NULL);
-            break;
+    case CURL_POLL_IN:
+        aio_set_fd_handler(s->aio_context, fd, false,
+                           curl_multi_read, NULL, NULL, state);
+        break;
+    case CURL_POLL_OUT:
+        aio_set_fd_handler(s->aio_context, fd, false,
+                           NULL, curl_multi_do, NULL, state);
+        break;
+    case CURL_POLL_INOUT:
+        aio_set_fd_handler(s->aio_context, fd, false,
+                           curl_multi_read, curl_multi_do, NULL, state);
+        break;
+    case CURL_POLL_REMOVE:
+        aio_set_fd_handler(s->aio_context, fd, false,
+                           NULL, NULL, NULL, NULL);
+        break;
     }
 
     return 0;
@@ -235,7 +236,7 @@ static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 /* Called from curl_multi_do_locked, with s->mutex held.  */
 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 {
-    CURLState *s = ((CURLState*)opaque);
+    CURLState *s = ((CURLState *)opaque);
     size_t realsize = size * nmemb;
     int i;
 
@@ -253,11 +254,12 @@ static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
     memcpy(s->orig_buf + s->buf_off, ptr, realsize);
     s->buf_off += realsize;
 
-    for(i=0; i<CURL_NUM_ACB; i++) {
+    for (i = 0; i < CURL_NUM_ACB; i++) {
         CURLAIOCB *acb = s->acb[i];
 
-        if (!acb)
+        if (!acb) {
             continue;
+        }
 
         if ((s->buf_off >= acb->end)) {
             size_t request_length = acb->bytes;
@@ -293,17 +295,16 @@ static bool curl_find_buf(BDRVCURLState *s, uint64_t start, uint64_t len,
     uint64_t clamped_end = MIN(end, s->len);
     uint64_t clamped_len = clamped_end - start;
 
-    for (i=0; i<CURL_NUM_STATES; i++) {
+    for (i = 0; i < CURL_NUM_STATES; i++) {
         CURLState *state = &s->states[i];
         uint64_t buf_end = (state->buf_start + state->buf_off);
         uint64_t buf_fend = (state->buf_start + state->buf_len);
 
-        if (!state->orig_buf)
-            continue;
-        if (!state->buf_off)
+        if (!state->orig_buf || !state->buf_off) {
             continue;
+        }
 
-        // Does the existing buffer cover our section?
+        /* Does the existing buffer cover our section? */
         if ((start >= state->buf_start) &&
             (start <= buf_end) &&
             (clamped_end >= state->buf_start) &&
@@ -319,7 +320,7 @@ static bool curl_find_buf(BDRVCURLState *s, uint64_t start, uint64_t len,
             return true;
         }
 
-        // Wait for unfinished chunks
+        /* Wait for unfinished chunks */
         if (state->in_use &&
             (start >= state->buf_start) &&
             (start <= buf_fend) &&
@@ -331,7 +332,7 @@ static bool curl_find_buf(BDRVCURLState *s, uint64_t start, uint64_t len,
             acb->start = start - state->buf_start;
             acb->end = acb->start + clamped_len;
 
-            for (j=0; j<CURL_NUM_ACB; j++) {
+            for (j = 0; j < CURL_NUM_ACB; j++) {
                 if (!state->acb[j]) {
                     state->acb[j] = acb;
                     return true;
@@ -355,8 +356,9 @@ static void curl_multi_check_completion(BDRVCURLState *s)
         msg = curl_multi_info_read(s->multi, &msgs_in_queue);
 
         /* Quit when there are no more completions */
-        if (!msg)
+        if (!msg) {
             break;
+        }
 
         if (msg->msg == CURLMSG_DONE) {
             CURLState *state = NULL;
@@ -540,12 +542,14 @@ static void curl_clean_state(CURLState *s)
 {
     CURLAIOCB *next;
     int j;
+
     for (j = 0; j < CURL_NUM_ACB; j++) {
         assert(!s->acb[j]);
     }
 
-    if (s->s->multi)
+    if (s->s->multi) {
         curl_multi_remove_handle(s->s->multi, s->curl);
+    }
 
     while (!QLIST_EMPTY(&s->sockets)) {
         CURLSocket *socket = QLIST_FIRST(&s->sockets);
@@ -794,7 +798,7 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
         goto out_noclean;
     }
 
-    // Get file size
+    /* Get file size */
 
     if (curl_init_state(s, state) < 0) {
         goto out;
@@ -802,11 +806,11 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
 
     s->accept_range = false;
     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
-    curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
-                     curl_header_cb);
+    curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION, curl_header_cb);
     curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
-    if (curl_easy_perform(state->curl))
+    if (curl_easy_perform(state->curl)) {
         goto out;
+    }
     if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d)) {
         goto out;
     }
@@ -876,13 +880,13 @@ static void curl_setup_preadv(BlockDriverState *bs, CURLAIOCB *acb)
 
     qemu_mutex_lock(&s->mutex);
 
-    // In case we have the requested data already (e.g. read-ahead),
-    // we can just call the callback and be done.
+    /* In case we have the requested data already (e.g. read-ahead),
+       we can just call the callback and be done. */
     if (curl_find_buf(s, start, acb->bytes, acb)) {
         goto out;
     }
 
-    // No cache found, so let's start a new request
+    /* No cache found, so let's start a new request */
     for (;;) {
         state = curl_find_state(s);
         if (state) {
-- 
2.9.5

Re: [Qemu-devel] [PATCH v2 3/7] block/sheepdog: remove spurious NULL check

[Philippe Mathieu-Daudé]

On Wed, Aug 30, 2017 at 1:57 PM, Jeff Cody <jcody@redhat.com> wrote:
> 'tag' is already checked in the lines immediately preceding this check,
> and set to non-NULL if NULL.  No need to check again, it hasn't changed.
>
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/sheepdog.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/block/sheepdog.c b/block/sheepdog.c
> index abb2e79..bbbfa72 100644
> --- a/block/sheepdog.c
> +++ b/block/sheepdog.c
> @@ -1632,7 +1632,7 @@ static int sd_open(BlockDriverState *bs, QDict *options, int flags,
>      if (!tag) {
>          tag = "";
>      }
> -    if (tag && strlen(tag) >= SD_MAX_VDI_TAG_LEN) {
> +    if (strlen(tag) >= SD_MAX_VDI_TAG_LEN) {

you can even prepend an 'else'! :D

>          error_setg(errp, "value of parameter 'tag' is too long");
>          ret = -EINVAL;
>          goto err_no_fd;
> --
> 2.9.5
>
>

Re: [Qemu-devel] [PATCH v2 1/7] block/ssh: don't call libssh2_init() in block_init()

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 1535 bytes --]

On 08/30/2017 11:56 AM, Jeff Cody wrote:
> We don't need libssh2 failure to be fatal (we could just opt to not
> register the driver on failure). But, it is probably a good idea to
> avoid external library calls during the block_init(), and call the
> libssh2 global init function on the first usage, returning any errors.
> 
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/ssh.c | 40 +++++++++++++++++++++++++++++-----------
>  1 file changed, 29 insertions(+), 11 deletions(-)
> 

> +static int ssh_state_init(BDRVSSHState *s, Error **errp)
>  {
> +    int ret;
> +
> +    if (!ssh_libinit_called) {
> +        ret = libssh2_init(0);
> +        if (ret) {
> +            error_setg(errp, "libssh2 initialization failed with %d", ret);
> +            return ret;

Do we know if this number is always positive or negative?

> @@ -772,8 +788,13 @@ static int ssh_file_open(BlockDriverState *bs, QDict *options, int bdrv_flags,
>      BDRVSSHState *s = bs->opaque;
>      int ret;
>      int ssh_flags;
> +    Error *local_err = NULL;
>  
> -    ssh_state_init(s);
> +    ret = ssh_state_init(s, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        return ret;

Is returning 'ret' from libssh2_init() wise?

If 'ret' is not important, you could simplify this:

if (ssh_state_init(s, errp)) {
    return -1;
}

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 2/7] block/ssh: make compliant with coding guidelines

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 383 bytes --]

On 08/30/2017 11:56 AM, Jeff Cody wrote:
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/ssh.c | 32 ++++++++++++++++++--------------
>  1 file changed, 18 insertions(+), 14 deletions(-)

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 3/7] block/sheepdog: remove spurious NULL check

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 508 bytes --]

On 08/30/2017 11:57 AM, Jeff Cody wrote:
> 'tag' is already checked in the lines immediately preceding this check,
> and set to non-NULL if NULL.  No need to check again, it hasn't changed.
> 
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/sheepdog.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 4/7] block/sheepdog: code beautification

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 3008 bytes --]

On 08/30/2017 11:57 AM, Jeff Cody wrote:
> No functional changes, just whitespace manipulation.
> 
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/sheepdog.c | 162 +++++++++++++++++++++++++++----------------------------
>  1 file changed, 81 insertions(+), 81 deletions(-)
> 

>  static BlockDriver bdrv_sheepdog = {
> -    .format_name    = "sheepdog",
> -    .protocol_name  = "sheepdog",
> -    .instance_size  = sizeof(BDRVSheepdogState),
> -    .bdrv_parse_filename    = sd_parse_filename,
> -    .bdrv_file_open = sd_open,
> -    .bdrv_reopen_prepare    = sd_reopen_prepare,
> -    .bdrv_reopen_commit     = sd_reopen_commit,
> -    .bdrv_reopen_abort      = sd_reopen_abort,
> -    .bdrv_close     = sd_close,
> -    .bdrv_create    = sd_create,
> -    .bdrv_has_zero_init = bdrv_has_zero_init_1,
> -    .bdrv_getlength = sd_getlength,

The existing style is indeed ugly since it has no consistency,...

> +    .format_name                  = "sheepdog",
> +    .protocol_name                = "sheepdog",
> +    .instance_size                = sizeof(BDRVSheepdogState),
> +    .bdrv_parse_filename          = sd_parse_filename,
> +    .bdrv_file_open               = sd_open,
> +    .bdrv_reopen_prepare          = sd_reopen_prepare,
> +    .bdrv_reopen_commit           = sd_reopen_commit,
> +    .bdrv_reopen_abort            = sd_reopen_abort,
> +    .bdrv_close                   = sd_close,
> +    .bdrv_create                  = sd_create,
> +    .bdrv_has_zero_init           = bdrv_has_zero_init_1,
> +    .bdrv_getlength               = sd_getlength,
>      .bdrv_get_allocated_file_size = sd_get_allocated_file_size,

...but aligning '=' requires mass reformatting if you get any longer
.bdrv_ function callback added down the road.  If it were me, I'd just
consistently use a single space everywhere, as in:

.format_name = "sheepdog",
.protocol_name = "sheepdog",

but that's my personal opinion, and not a hard rule, so I won't be
bothered if you don't take it.

>  static BlockDriver bdrv_sheepdog_tcp = {
> -    .format_name    = "sheepdog",
> -    .protocol_name  = "sheepdog+tcp",
> -    .instance_size  = sizeof(BDRVSheepdogState),
> -    .bdrv_parse_filename    = sd_parse_filename,
> +    .format_name                  = "sheepdog",
> +    .protocol_name                = "sheepdog+tcp",
> +    .instance_size                = sizeof(BDRVSheepdogState),
> +    .bdrv_parse_filename          = sd_parse_filename,
>      .bdrv_file_open = sd_open,

See, with your style, this row now stands out as being missed; with my
style, this line needs no edits.

But your changes are indeed semantic no-ops, so whether you fix the few
unaligned lines per your style, or redo to a consistent style of only a
single space, you can add:
Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 5/7] block/curl: check error return of curl_global_init()

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 738 bytes --]

On 08/30/2017 11:57 AM, Jeff Cody wrote:
> If curl_global_init() fails, per the documentation no other curl
> functions may be called, so make sure to check the return value.
> 
> Also, some minor changes to the initialization latch variable 'inited':
> 
> - Make it static in the file, for clarity
> - Change the name for clarity
> - Make it a bool
> 
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/curl.c | 18 ++++++++++++------
>  1 file changed, 12 insertions(+), 6 deletions(-)
> 
> diff --git a/block/curl.c b/block/curl.c

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 6/7] block/curl: fix minor memory leaks

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 922 bytes --]

On 08/30/2017 11:57 AM, Jeff Cody wrote:
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/curl.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 

> +++ b/block/curl.c
> @@ -857,6 +857,9 @@ out_noclean:
>      qemu_mutex_destroy(&s->mutex);
>      g_free(s->cookie);
>      g_free(s->url);
> +    g_free(s->username);
> +    g_free(s->proxyusername);
> +    g_free(s->proxypassword);

Would it be any simpler to call curl_close(s) instead of open-coding it
here in this cleanup path?

> @@ -955,6 +958,9 @@ static void curl_close(BlockDriverState *bs)
>  
>      g_free(s->cookie);
>      g_free(s->url);
> +    g_free(s->username);
> +    g_free(s->proxyusername);
> +    g_free(s->proxypassword);
>  }

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 7/7] block/curl: code cleanup to comply with coding style

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 2351 bytes --]

On 08/30/2017 11:57 AM, Jeff Cody wrote:
> This addresses non-functional changes to help curl.c better comply
> with the coding styles (comments, indentation, brackets, etc.).
> 
> One minor code change is the combination of two if statements into
> a single if statement.
> 
> Signed-off-by: Jeff Cody <jcody@redhat.com>
> ---
>  block/curl.c | 100 +++++++++++++++++++++++++++++++----------------------------
>  1 file changed, 52 insertions(+), 48 deletions(-)
> 

> -#define CURL_BLOCK_OPT_URL       "url"
> -#define CURL_BLOCK_OPT_READAHEAD "readahead"
> -#define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
> -#define CURL_BLOCK_OPT_TIMEOUT "timeout"
> -#define CURL_BLOCK_OPT_COOKIE    "cookie"
> -#define CURL_BLOCK_OPT_COOKIE_SECRET "cookie-secret"
> -#define CURL_BLOCK_OPT_USERNAME "username"
> -#define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
> -#define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"

Another change from inconsistent spacing,

> +#define CURL_BLOCK_OPT_URL                   "url"
> +#define CURL_BLOCK_OPT_READAHEAD             "readahead"
> +#define CURL_BLOCK_OPT_SSLVERIFY             "sslverify"
> +#define CURL_BLOCK_OPT_TIMEOUT               "timeout"
> +#define CURL_BLOCK_OPT_COOKIE                "cookie"
> +#define CURL_BLOCK_OPT_COOKIE_SECRET         "cookie-secret"
> +#define CURL_BLOCK_OPT_USERNAME              "username"
> +#define CURL_BLOCK_OPT_PASSWORD_SECRET       "password-secret"
> +#define CURL_BLOCK_OPT_PROXY_USERNAME        "proxy-username"
>  #define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"

to something that is consistent but requires a mass-edit if we add a
longer name.


> @@ -235,7 +236,7 @@ static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
>  /* Called from curl_multi_do_locked, with s->mutex held.  */
>  static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
>  {
> -    CURLState *s = ((CURLState*)opaque);
> +    CURLState *s = ((CURLState *)opaque);

Umm, this is C, so why not just:

CURLState *s = opaque;

Those are minor findings, so whether or not you address them,
Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 1/7] block/ssh: don't call libssh2_init() in block_init()

[Jeff Cody]

On Wed, Aug 30, 2017 at 02:40:16PM -0500, Eric Blake wrote:
> On 08/30/2017 11:56 AM, Jeff Cody wrote:
> > We don't need libssh2 failure to be fatal (we could just opt to not
> > register the driver on failure). But, it is probably a good idea to
> > avoid external library calls during the block_init(), and call the
> > libssh2 global init function on the first usage, returning any errors.
> > 
> > Signed-off-by: Jeff Cody <jcody@redhat.com>
> > ---
> >  block/ssh.c | 40 +++++++++++++++++++++++++++++-----------
> >  1 file changed, 29 insertions(+), 11 deletions(-)
> > 
> 
> > +static int ssh_state_init(BDRVSSHState *s, Error **errp)
> >  {
> > +    int ret;
> > +
> > +    if (!ssh_libinit_called) {
> > +        ret = libssh2_init(0);
> > +        if (ret) {
> > +            error_setg(errp, "libssh2 initialization failed with %d", ret);
> > +            return ret;
> 
> Do we know if this number is always positive or negative?
> 

>From the documentation [1], it returns 0 on success, or a negative value
for error.  (I guess presumably that means a positive value is by definition
an error, as well).

[1] https://www.libssh2.org/libssh2_init.html

> > @@ -772,8 +788,13 @@ static int ssh_file_open(BlockDriverState *bs, QDict *options, int bdrv_flags,
> >      BDRVSSHState *s = bs->opaque;
> >      int ret;
> >      int ssh_flags;
> > +    Error *local_err = NULL;
> >  
> > -    ssh_state_init(s);
> > +    ret = ssh_state_init(s, &local_err);
> > +    if (local_err) {
> > +        error_propagate(errp, local_err);
> > +        return ret;
> 
> Is returning 'ret' from libssh2_init() wise?
> 
> If 'ret' is not important, you could simplify this:
> 
> if (ssh_state_init(s, errp)) {
>     return -1;
> }

Good point, not sure if a non-zero ret from libssh2_init() provides meaning
beyond 'error' for us.  Maybe return -EIO instead of -1, though?

Re: [Qemu-devel] [PATCH v2 1/7] block/ssh: don't call libssh2_init() in block_init()

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 970 bytes --]

On 08/30/2017 03:11 PM, Jeff Cody wrote:
> On Wed, Aug 30, 2017 at 02:40:16PM -0500, Eric Blake wrote:
>> On 08/30/2017 11:56 AM, Jeff Cody wrote:
>>> We don't need libssh2 failure to be fatal (we could just opt to not
>>> register the driver on failure). But, it is probably a good idea to
>>> avoid external library calls during the block_init(), and call the
>>> libssh2 global init function on the first usage, returning any errors.
>>>

>>
>> Is returning 'ret' from libssh2_init() wise?
>>
>> If 'ret' is not important, you could simplify this:
>>
>> if (ssh_state_init(s, errp)) {
>>     return -1;
>> }
> 
> Good point, not sure if a non-zero ret from libssh2_init() provides meaning
> beyond 'error' for us.  Maybe return -EIO instead of -1, though?

You used -EIO for 5/7, so that does sound a bit better.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 619 bytes --]

Re: [Qemu-devel] [PATCH v2 1/7] block/ssh: don't call libssh2_init() in block_init()

[Richard W.M. Jones]

On Wed, Aug 30, 2017 at 02:40:16PM -0500, Eric Blake wrote:
> On 08/30/2017 11:56 AM, Jeff Cody wrote:
> > We don't need libssh2 failure to be fatal (we could just opt to not
> > register the driver on failure). But, it is probably a good idea to
> > avoid external library calls during the block_init(), and call the
> > libssh2 global init function on the first usage, returning any errors.
> > 
> > Signed-off-by: Jeff Cody <jcody@redhat.com>
> > ---
> >  block/ssh.c | 40 +++++++++++++++++++++++++++++-----------
> >  1 file changed, 29 insertions(+), 11 deletions(-)
> > 
> 
> > +static int ssh_state_init(BDRVSSHState *s, Error **errp)
> >  {
> > +    int ret;
> > +
> > +    if (!ssh_libinit_called) {
> > +        ret = libssh2_init(0);
> > +        if (ret) {
> > +            error_setg(errp, "libssh2 initialization failed with %d", ret);
> > +            return ret;
> 
> Do we know if this number is always positive or negative?

FWIW documentation says:

  "Returns 0 if succeeded, or a negative value for error."

I was holding off on reviewing this patch in general since there's a
libssh-based alternative driver under development, which should be
better.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into KVM guests.
http://libguestfs.org/virt-v2v