Skip to content
GitLab
Explore
Sign in
Primary navigation
Search or go to…
Project
T
TLMSP curl
Manage
Activity
Members
Labels
Plan
Issues
Issue boards
Milestones
Wiki
Code
Merge requests
Repository
Branches
Commits
Tags
Repository graph
Compare revisions
Snippets
Build
Pipelines
Jobs
Pipeline schedules
Artifacts
Deploy
Releases
Package registry
Container Registry
Model registry
Operate
Environments
Terraform modules
Monitor
Incidents
Analyze
Value stream analytics
Contributor analytics
CI/CD analytics
Repository analytics
Model experiments
Help
Help
Support
GitLab documentation
Compare GitLab plans
Community forum
Contribute to GitLab
Provide feedback
Keyboard shortcuts
?
Snippets
Groups
Projects
Show more breadcrumbs
CYBER - Cyber Security
TS 103 523 MSP
TLMSP
TLMSP curl
Commits
dc11239f
Commit
dc11239f
authored
17 years ago
by
Daniel Stenberg
Browse files
Options
Downloads
Patches
Plain Diff
slightly less outdated
parent
d5984161
No related branches found
Branches containing commit
No related tags found
Tags containing commit
No related merge requests found
Changes
1
Hide whitespace changes
Inline
Side-by-side
Showing
1 changed file
docs/INTERNALS
+23
-20
23 additions, 20 deletions
docs/INTERNALS
with
23 additions
and
20 deletions
docs/INTERNALS
+
23
−
20
View file @
dc11239f
...
...
@@ -97,7 +97,9 @@ Library
... analyzes the URL, it separates the different components and connects to
the remote host. This may involve using a proxy and/or using SSL. The
Curl_gethost() function in lib/hostip.c is used for looking up host names.
Curl_resolv() function in lib/hostip.c is used for looking up host names
(it does then use the proper underlying method, which may vary between
platforms and builds).
When Curl_connect is done, we are connected to the remote site. Then it is
time to tell the server to get a document/file. Curl_do() arranges this.
...
...
@@ -122,17 +124,20 @@ Library
Curl_Transfer() function (in lib/transfer.c) to setup the transfer and
returns.
Starting in 7.9.1, if this DO function fails and the connection is being
re-used, libcurl will then close this connection, setup a new connection
and re-issue the DO request on that. This is because there is no way to be
perfectly sure that we have discovered a dead connection before the DO
function and thus we might wrongly be re-using a connection that was closed
by the remote peer.
If this DO function fails and the connection is being re-used, libcurl will
then close this connection, setup a new connection and re-issue the DO
request on that. This is because there is no way to be perfectly sure that
we have discovered a dead connection before the DO function and thus we
might wrongly be re-using a connection that was closed by the remote peer.
Some time during the DO function, the Curl_setup_transfer() function must
be called with some basic info about the upcoming transfer: what socket(s)
to read/write and the expected file tranfer sizes (if known).
o Transfer()
Curl_perform() then calls Transfer() in lib/transfer.c that performs
the
entire file transfer.
Curl_perform() then calls Transfer() in lib/transfer.c that performs
the
entire file transfer.
During transfer, the progress functions in lib/progress.c are called at a
frequent interval (or at the user's choice, a specified callback might get
...
...
@@ -236,9 +241,8 @@ Library
URL encoding and decoding, called escaping and unescaping in the source code,
is found in lib/escape.c.
While transfering data in Transfer() a few functions might get
used. curl_getdate() in lib/getdate.c is for HTTP date comparisons (and
more).
While transfering data in Transfer() a few functions might get used.
curl_getdate() in lib/parsedate.c is for HTTP date comparisons (and more).
lib/getenv.c offers curl_getenv() which is for reading environment variables
in a neat platform independent way. That's used in the client, but also in
...
...
@@ -254,10 +258,6 @@ Library
A function named curl_version() that returns the full curl version string is
found in lib/version.c.
If authentication is requested but no password is given, a getpass_r() clone
exists in lib/getpass.c. libcurl offers a custom callback that can be used
instead of this, but it doesn't change much to us.
Persistent Connections
======================
...
...
@@ -269,9 +269,11 @@ Persistent Connections
all the options etc that the library-user may choose.
o The 'SessionHandle' struct holds the "connection cache" (an array of
pointers to 'connectdata' structs). There's one connectdata struct
allocated for each connection that libcurl knows about.
o This also enables the 'curl handle' to be reused on subsequent transfers,
something that was illegal before libcurl 7.7.
allocated for each connection that libcurl knows about. Note that when you
use the multi interface, the multi handle will hold the connection cache
and not the particular easy handle. This of course to allow all easy handles
in a multi stack to be able to share and re-use connections.
o This enables the 'curl handle' to be reused on subsequent transfers.
o When we are about to perform a transfer with curl_easy_perform(), we first
check for an already existing connection in the cache that we can use,
otherwise we create a new one and add to the cache. If the cache is full
...
...
@@ -281,7 +283,8 @@ Persistent Connections
o When the transfer operation is complete, we try to leave the connection
open. Particular options may tell us not to, and protocols may signal
closure on connections and then we don't keep it open of course.
o When curl_easy_cleanup() is called, we close all still opened connections.
o When curl_easy_cleanup() is called, we close all still opened connections,
unless of course the multi interface "owns" the connections.
You do realize that the curl handle must be re-used in order for the
persistent connections to work.
...
...
This diff is collapsed.
Click to expand it.
Preview
0%
Loading
Try again
or
attach a new file
.
Cancel
You are about to add
0
people
to the discussion. Proceed with caution.
Finish editing this message first!
Save comment
Cancel
Please
register
or
sign in
to comment