From: Charles Plessy Date: Tue, 12 Oct 2010 15:14:42 +0000 (+0900) Subject: Clarification of the format of control files, Closes: #501930, #593909. X-Git-Url: https://git.donarmstrong.com/?p=debian%2Fdebian-policy.git;a=commitdiff_plain;h=0ecd2cf30502d7e428b3ee6637c1ca5909fdefaa Clarification of the format of control files, Closes: #501930, #593909. - Specifies field names similarly to RFC 822/5832; - Distinguishes simple, folded and mulitiline fields; - Clarifies paragraph separators (#501930); - The order of paragraphs is significant; - Fields can have different types or purposes in different control files; - Moved the description of comments from §5.2 to §5.1; - Documented that relationship fields can only be folded in debian/control. --- diff --git a/policy.sgml b/policy.sgml index ec605c6..91173a5 100644 --- a/policy.sgml +++ b/policy.sgml @@ -2479,19 +2479,26 @@ endif fields The paragraphs are also sometimes referred to as stanzas. . - The paragraphs are separated by blank lines. Some control + The paragraphs are separated by empty lines. Parsers may accept + lines consisting solely of spaces and tabs as paragraph + separators, but control files should use empty lines. Some control files allow only one paragraph; others allow several, in which case each paragraph usually refers to a different package. (For example, in source packages, the first paragraph refers to the source package, and later paragraphs - refer to binary packages generated from the source.) + refer to binary packages generated from the source.) The + ordering of the paragraphs in control files is significant.

Each paragraph consists of a series of data fields; each field consists of the field name, followed by a colon and - then the data/value associated with that field. It ends at - the end of the (logical) line. Horizontal whitespace + then the data/value associated with that field. The field + name is composed of printable ASCII characters (i.e., + characters that have values between 33 and 126, inclusive) + except colon and must not with a begin with #. The + field ends at the end of the line or at the end of the + last continuation line (see below). Horizontal whitespace (spaces and tabs) may occur immediately before or after the value and is ignored there; it is conventional to put a single space after the colon. For example, a field might @@ -2509,21 +2516,51 @@ Package: libc6

- Many fields' values may span several lines; in this case - each continuation line must start with a space or a tab. - Any trailing spaces or tabs at the end of individual - lines of a field value are ignored. + There are three types of fields: + + simple + + The field, including its value, must be a single line. Folding + of the field is not permitted. This is the default field type + if the definition of the field does not specify a different + type. + + folded + + The value of a folded field is a logical line that may span + several lines. The lines after the first are called + continuation lines and must start with a space or a tab. + Whitespace, including any newlines, is not significant in the + field values of folded fields. + This folding method is similar to RFC 5322, allowing control + files that contain only one paragraph and no multiline fields + to be read by parsers written for RFC 5322. + + + multiline + + The value of a multiline field may comprise multiple continuation + lines. The first line of the value, the part on the same line as + the field name, often has special significance or may have to be + empty. Other lines are added following the same syntax as the + continuation lines the folded fields. Whitespace, including newlines, + is significant in the values of multiline fields. + +

- In fields where it is specified that lines may not wrap, - only a single line of data is allowed and whitespace is not - significant in a field body. Whitespace must not appear + Whitespace must not appear inside names (of packages, architectures, files or anything else) or version numbers, or between the characters of multi-character version relationships.

+

+ The presence and purpose of a field, and the syntax of its + value may differ between types of control files. +

+

Field names are not case-sensitive, but it is usual to capitalize the field names using mixed case as shown below. @@ -2532,9 +2569,17 @@ Package: libc6

- Blank lines, or lines consisting only of spaces and tabs, - are not allowed within field values or between fields - that - would mean a new paragraph. + Paragraph separators (empty lines) and lines consisting only of + spaces and tabs are not allowed within field values or between + fields. Empty lines in field values are usually escaped by + representing them by a space followed by a dot. +

+ +

+ Lines starting with # without any preceding whitespace are comments + lines that are only permitted in source package control files + (debian/control). These comment lines are ignored, even + between two continuation lines. They do not end logical lines.

@@ -2600,8 +2645,8 @@ Package: libc6 .changes file to accompany the upload, and by dpkg-source when it creates the .dsc source control file as part of a source - archive. Many fields are permitted to span multiple lines in - debian/control but not in any other control + archive. Some fields are folded in debian/control, + but not in any other control file. These tools are responsible for removing the line breaks from such fields when using fields from debian/control to generate other control files. @@ -2614,16 +2659,6 @@ Package: libc6 when they generate output control files. See for details.

- -

- In addition to the control file syntax described above, this file may also contain - comment lines starting with # without any preceding - whitespace. All such lines are ignored, even in the middle of - continuation lines for a multiline field, and do not end a - multiline field. -

- @@ -2822,11 +2857,7 @@ Package: libc6

- Any parser that interprets the Uploaders field in - debian/control must permit it to span multiple - lines. Line breaks in an Uploaders field that spans multiple - lines are not significant and the semantics of the field are - the same as if the line breaks had not been present. + The Uploaders field in debian/control can be folded.

@@ -3006,7 +3037,7 @@ Package: libc6

This is a boolean field which may occur only in the control file of a binary package or in a per-package fields - paragraph of a main source control data file. + paragraph of a source package control file.

@@ -3242,7 +3273,8 @@ Package: libc6 In a source or binary control file, the Description field contains a description of the binary package, consisting of two parts, the synopsis or the short description, and the - long description. The field's format is as follows: + long description. It is a multiline field with the following + format:

@@ -3306,8 +3338,8 @@ Package: libc6 field contains a summary of the descriptions for the packages being uploaded. For this case, the first line of the field value (the part on the same line as Description:) is - always empty. The content of the field is expressed as - continuation lines, one line per package. Each line is + always empty. It is a multiline field, with one + line per package. Each line is indented by one space and contains the name of a binary package, a space, a hyphen (-), a space, and the short description line from that package. @@ -3443,7 +3475,7 @@ Package: libc6 Changes

- This field contains the human-readable changes data, describing + This multiline field contains the human-readable changes data, describing the differences between the last version and the current one.

@@ -3481,7 +3513,7 @@ Package: libc6 Binary

- This field is a list of binary packages. Its syntax and + This folded field is a list of binary packages. Its syntax and meaning varies depending on the control file in which it appears.

@@ -3491,7 +3523,7 @@ Package: libc6 packages which a source package can produce, separated by commas A space after each comma is conventional. - . It may span multiple lines. The source package + . The source package does not necessarily produce all of these binary packages for every architecture. The source control file doesn't contain details of which architectures are appropriate for which of @@ -3501,7 +3533,7 @@ Package: libc6

When it appears in a .changes file, it lists the names of the binary packages being uploaded, separated by - whitespace (not commas). It may span multiple lines. + whitespace (not commas).

@@ -3624,7 +3656,7 @@ Files: and Checksums-Sha256

- These fields contain a list of files with a checksum and size + These multiline fields contain a list of files with a checksum and size for each one. Both Checksums-Sha1 and Checksums-Sha256 have the same syntax and differ only in the checksum algorithm used: SHA-1 @@ -4562,13 +4594,13 @@ fi specification subject to the rules in , and must appear where it's necessary to disambiguate; it is not otherwise significant. All of the - relationship fields may span multiple lines. For + relationship fields can only be folded in source package control files. For consistency and in case of future changes to dpkg it is recommended that a single space be used after a version relationship and before a version number; it is also conventional to put a single space after each comma, on either side of each vertical bar, and before - each open parenthesis. When wrapping a relationship field, it + each open parenthesis. When opening a continuation line in a relationship field, it is conventional to do so after a comma and before the space following that comma.