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Diffstat (limited to 'third_party/git/Documentation/technical/api-error-handling.txt')
-rw-r--r-- | third_party/git/Documentation/technical/api-error-handling.txt | 75 |
1 files changed, 0 insertions, 75 deletions
diff --git a/third_party/git/Documentation/technical/api-error-handling.txt b/third_party/git/Documentation/technical/api-error-handling.txt deleted file mode 100644 index ceeedd485c96..000000000000 --- a/third_party/git/Documentation/technical/api-error-handling.txt +++ /dev/null @@ -1,75 +0,0 @@ -Error reporting in git -====================== - -`die`, `usage`, `error`, and `warning` report errors of various -kinds. - -- `die` is for fatal application errors. It prints a message to - the user and exits with status 128. - -- `usage` is for errors in command line usage. After printing its - message, it exits with status 129. (See also `usage_with_options` - in the link:api-parse-options.html[parse-options API].) - -- `error` is for non-fatal library errors. It prints a message - to the user and returns -1 for convenience in signaling the error - to the caller. - -- `warning` is for reporting situations that probably should not - occur but which the user (and Git) can continue to work around - without running into too many problems. Like `error`, it - returns -1 after reporting the situation to the caller. - -Customizable error handlers ---------------------------- - -The default behavior of `die` and `error` is to write a message to -stderr and then exit or return as appropriate. This behavior can be -overridden using `set_die_routine` and `set_error_routine`. For -example, "git daemon" uses set_die_routine to write the reason `die` -was called to syslog before exiting. - -Library errors --------------- - -Functions return a negative integer on error. Details beyond that -vary from function to function: - -- Some functions return -1 for all errors. Others return a more - specific value depending on how the caller might want to react - to the error. - -- Some functions report the error to stderr with `error`, - while others leave that for the caller to do. - -- errno is not meaningful on return from most functions (except - for thin wrappers for system calls). - -Check the function's API documentation to be sure. - -Caller-handled errors ---------------------- - -An increasing number of functions take a parameter 'struct strbuf *err'. -On error, such functions append a message about what went wrong to the -'err' strbuf. The message is meant to be complete enough to be passed -to `die` or `error` as-is. For example: - - if (ref_transaction_commit(transaction, &err)) - die("%s", err.buf); - -The 'err' parameter will be untouched if no error occurred, so multiple -function calls can be chained: - - t = ref_transaction_begin(&err); - if (!t || - ref_transaction_update(t, "HEAD", ..., &err) || - ret_transaction_commit(t, &err)) - die("%s", err.buf); - -The 'err' parameter must be a pointer to a valid strbuf. To silence -a message, pass a strbuf that is explicitly ignored: - - if (thing_that_can_fail_in_an_ignorable_way(..., &err)) - /* This failure is okay. */ - strbuf_reset(&err); |